Free Web Tools
A growing set of fast, private utilities that run entirely in your browser — what you enter never leaves your device. Built by Patrick Bushe.
Weighted Average Calculator
Free weighted average calculator: combine values with their weights into a single weighted mean, computed in your browser.
Open ToolWheel Offset Change Calculator
Calculate the offset change and poke from a new and old wheel offset. Everything is calculated locally in your browser, with no uploads or sign-ups.
Open ToolWildcard Mask Calculator
Free wildcard mask calculator: convert a subnet mask to the inverse wildcard mask used in ACLs, computed locally in your browser.
Open ToolWind Chill Calculator
Free wind chill calculator using the official formula: enter temperature and wind speed to get the feels-like temperature, in your browser.
Open ToolWindow Film Area Calculator
Calculate total window film area from a window count and area each. Everything is calculated locally in your browser, with no uploads or sign-ups.
Open ToolWine Bottle Servings Calculator
Free wine bottle servings calculator with labeled inputs and an immediate result. It estimates pours from bottle and serving sizes privately in your browser.
Open ToolWine Servings Calculator
Calculate standard servings from bottle volume and pour size with quick private arithmetic. It runs entirely in your browser, with no uploads or accounts.
Open ToolWorkdays in a Month Calculator
Free workdays in a month calculator: count the weekdays and weekend days in any month, computed locally in your browser.
Open ToolXml Tag Wrapper
Wrap text values in XML tags with attributes and indentation controls. A sitemap-like snippet can wrap loc and lastmod values in url elements.
Open ToolXML to CSV Converter
Free XML to CSV converter that parses balanced markup, finds repeated row elements, unions child columns, and quotes CSV values in your browser.
Open ToolXpath Tester
Test XPath in your browser with a live preview and one-click copy — free and private, generated locally in your browser with no upload and no account needed.
Open ToolYAML Frontmatter
Convert YAML frontmatter in your browser with a live preview and one-click copy. It runs entirely client-side, so nothing is uploaded and no account is needed.
Open ToolYes or No Generator
Free yes or no generator: get a random yes, no, or maybe to settle a decision, drawn instantly in your browser.
Open ToolZ-Score Calculator
Free z-score calculator: find how many standard deviations a value sits from the mean, computed locally in your browser.
Open ToolZ-Score to Percentile Calculator
Free z-score to percentile calculator: convert a z-score to its percentile under the normal curve, in your browser.
Open ToolAccept Language Header
Generate Accept-Language header values with q weights for locale testing. A localization test can send en-US first, then en, then es with lower weights.
Open ToolAcres to Hectares Converter
Convert acres to hectares and hectares to acres using the international area relationship, with six-significant-figure results in your browser.
Open ToolAd Frequency Calculator
Calculate average ad frequency by dividing total impressions by unique reach. Everything is calculated locally in your browser, with no uploads or sign-ups.
Open ToolAdditive Grade Curve
Free additive grade curve calculator that shifts every score by the same points until the highest reaches 100, calculated privately in your browser.
Open ToolAPI Error Response
Work with API error response in your browser with a live preview and one-click copy — free and private, generated locally in your browser with no upload and.
Open ToolAPY to APR Converter
Convert APY to nominal APR for a selected compounding frequency with transparent local math. It runs entirely in your browser, with no uploads or accounts.
Open ToolAtoms to Moles Calculator
Free atoms to moles calculator: convert between a number of particles and moles using Avogadro’s number, in your browser.
Open ToolAxios Request
Work with axios request in your browser with a live preview and one-click copy. It runs entirely client-side, so nothing is uploaded and no account is needed.
Open ToolBalloon Loan Calculator
Calculate interest-only balloon loan payments, total paid before maturity, and final balance. It runs entirely in your browser, with no uploads or accounts.
Open ToolBase-N Converter
Free base-N number converter: convert a number between any bases from 2 to 36, computed locally in your browser.
Open ToolBase62 Encoder & Decoder
Free Base62 converter: encode a number to Base62 and decode it back, using digits and letters, in your browser.
Open ToolBase64 Url Encoder Decoder
Encode and decode base64url strings for tokens, payloads, and compact IDs. A JWT segment can be decoded after replacing URL-safe characters and padding.
Open ToolBody Surface Area Calculator
Free body surface area calculator with labeled inputs and an immediate result. It estimates adult body surface area with Mosteller privately in your browser.
Open ToolBond Current Yield Calculator
Free bond current yield calculator with labeled inputs and an immediate result. It compares annual coupon income with market price privately in your browser.
Open ToolBrine Percentage Calculator
Free brine percentage calculator with labeled inputs and an immediate result. It calculates salt as a percentage of water weight privately in your browser.
Open ToolBundle Price Calculator
Calculate a bundle price and savings from the separate item total and a discount. Everything is calculated locally in your browser, with no uploads or sign-ups.
Open ToolCalories Activity MET Calculator
Calculate calories burned from MET value, body weight, and minutes with the standard exercise formula. It runs locally in your browser with no uploads.
Open ToolCapacitors in Series Calculator
Calculate equivalent capacitance for any positive list of series capacitor values and inspect the reciprocal sum privately in your browser safely now.
Open ToolCapitalize Each Word
Free tool to capitalize the first letter of every word (title case), computed locally in your browser.
Open ToolCelsius to Fahrenheit Converter
Convert Celsius to Fahrenheit and Fahrenheit to Celsius with the exact affine formulas and clear six-significant-figure results in your browser.
Open ToolCoffee Brew Water Calculator
Calculate coffee and water grams from brew ratio and desired cups with private kitchen math. It runs entirely in your browser, with no uploads or accounts.
Open ToolCollatz Sequence Calculator
Free Collatz sequence calculator that applies the odd and even rules, lists every term, and reports step count and peak privately in your browser.
Open ToolColor Border Shadow Palette
Generate border and shadow colors from a base surface color. A white modal can get a cool gray border and soft shadow token from the same base.
Open ToolColor Calendar Heatmap Palette
Generate calendar heatmap colors for low-to-high activity levels with a live preview and one-click copy. Free and private, with nothing uploaded to any server.
Open ToolColor CSS Variable Theme Diff
Compare two sets of CSS color variables and list changed, added, and removed tokens. Free and private in your browser, with nothing uploaded and no account.
Open ToolColor Opacity Scale
Generate color opacity scale in your browser with a live preview and one-click copy — free and private, generated locally in your browser with no upload and.
Open ToolColor State Layer
Generate color state layer in your browser with a live preview and one-click copy — free and private, generated locally in your browser with no upload and no.
Open ToolColor Status Token Crosswalk
Map success, warning, danger, info, and neutral statuses to CSS color tokens. Free and private in your browser, with nothing uploaded and no account.
Open ToolColor Temperature Palette
Generate color temperature palette in your browser with a live preview and one-click copy — free and private, generated locally in your browser with no upload.
Open ToolColor Ui Surface Pair Checker
Preview foreground, muted text, border, and accent colors on a chosen UI surface. Free and private in your browser, with nothing uploaded and no account.
Open ToolContribution Margin Calculator
Free contribution margin calculator: find the amount and percentage each sale contributes after variable costs, computed in your browser.
Open ToolCookie Header
Build Set-Cookie header strings with SameSite, Secure, HttpOnly, and Max-Age options. Free and private in your browser, with nothing uploaded and no account.
Open ToolCookie Header Parser
Free Cookie header parser that handles semicolon pairs, quoted values, empty values, and percent decoding into structured JSON in your browser.
Open ToolCookie Policy Generator
Write a cookie policy that lists essential, analytics, marketing, and preference cookies with provider names, contact details, and local export.
Open ToolCountdown to a Date
Free live countdown to any date and time: see days, hours, minutes, and seconds remaining, ticking in your browser.
Open ToolCSS Animation Delay Stagger
Create nth-child animation delays for staggered cards, menu items, and lists. A ten-item menu can reveal each row 80ms after the previous row.
Open ToolCSS Any Hover Query
Build any-hover media query snippets for mixed-input laptops and tablets. Everything runs locally in your browser with nothing uploaded and no account needed.
Open ToolCSS Caret Color
Preview caret-color for form fields, editors, and themed input states. A dark search box can use a bright brand caret while keeping the typed text white.
Open ToolCSS Class Name Cleaner
Clean pasted class names into lowercase, hyphenated, reusable CSS identifiers. A label like Primary CTA Button can become primary-cta-button.
Open ToolCSS Column Rule
Generate column-rule CSS for visual separators in multi-column text. A newsletter archive can add a light rule between two text columns. Free, in your browser.
Open ToolCSS Counter Style
Build CSS counter-reset and counter-increment snippets for numbered sections. Free and private in your browser, with nothing uploaded and no account.
Open ToolCSS Coupon Card
Build CSS coupon card in your browser with a live preview and one-click copy. Free and private: everything is generated locally in your browser with no upload.
Open ToolCSS Details Marker
Targets summary and summary::marker, then adds spacing and color rules around the native disclosure control. Free and private — nothing is uploaded.
Open ToolCSS Field Sizing
Preview field-sizing content for textareas that grow to fit typed content. Everything runs locally in your browser with nothing uploaded and no account needed.
Open ToolCSS Fluid Spacing Token
Build clamp-based spacing tokens for responsive margins, gaps, and section padding. Free and private in your browser, with nothing uploaded and no account.
Open ToolCSS Focus Visible Style
Create :focus-visible outlines for keyboard navigation without noisy mouse focus rings. Free and private in your browser, with nothing uploaded and no account.
Open ToolCSS Font Stack Builder
Use this free CSS font stack builder in your browser to assemble an ordered quoted font-family fallback stack. Output stays private and local.
Open ToolCSS Forced Colors
Preview forced-colors CSS for Windows high contrast mode adaptations. A custom button can restore a visible border and use CanvasText in forced colors.
Open ToolCSS Form Input
Build CSS form input in your browser with a live preview and one-click copy. Free and private: everything is generated locally in your browser with no upload.
Open ToolCSS Full Height Panel
Build CSS full height panel in your browser with a live preview and one-click copy — free and private, generated locally in your browser with no upload and no.
Open ToolCSS Hover Media Query
Generate hover media queries for mouse, stylus, and touch-first interfaces. A card hover shadow can be limited to devices where hover actually exists.
Open ToolCSS Map Pin
Build CSS map pin in your browser with a live preview and one-click copy. Free and private: everything is generated locally in your browser with no upload.
Open ToolCSS Masonry Layout
Build CSS masonry layout in your browser with a live preview and one-click copy. It runs entirely client-side, so nothing is uploaded and no account is needed.
Open ToolCSS Max Lines Fade
Create line-clamp style snippets with a fade overlay for excerpt cards. A blog teaser can show three lines of text with a soft fade at the bottom edge.
Open ToolCSS Outline Offset
Create focus outline and outline-offset CSS for buttons, cards, and links. Everything runs locally in your browser with nothing uploaded and no account needed.
Open ToolCSS Page Size
Create page size and margin CSS for printable documents and handouts with a live preview and one-click copy. Free and private — nothing is uploaded.
Open ToolCSS Pricing Card
Work with CSS pricing card in your browser with a live preview and one-click copy — free and private, generated locally in your browser with no upload and no.
Open ToolCSS Range Input Style
Generate range slider track and thumb styles for common browsers. A volume slider can use a green thumb and muted track that match the app theme.
Open ToolCSS Resize Property
Preview CSS resize handles for textareas, panels, and debugging boxes with a live preview and one-click copy. Free and private — nothing is uploaded.
Open ToolCSS Scroll Snap Align
Preview scroll-snap-align choices for cards inside horizontal scrollers. A carousel can center each product card when the user finishes scrolling.
Open ToolCSS Scroll Timeline Range
Preview scroll animation range values for elements tied to page scroll with a live preview and one-click copy. Free and private — nothing is uploaded.
Open ToolCSS Scrollbar Width
Preview scrollbar-width values for compact panels and code blocks. A narrow sidebar can use a thin scrollbar without custom WebKit styling. In your browser.
Open ToolCSS Sticky Sidebar
Build CSS sticky sidebar in your browser with a live preview and one-click copy. It runs entirely client-side, so nothing is uploaded and no account is needed.
Open ToolCSS Stripe Background Generator
Generate CSS stripe background in your browser with a live preview and one-click copy — free and private, generated locally in your browser with no upload and.
Open ToolCSS Subgrid Playground
Preview subgrid track inheritance for nested card content and aligned forms. Free and private in your browser, with nothing uploaded and no account.
Open ToolCSS Testimonial Card
Build CSS testimonial card in your browser with a live preview and one-click copy — free and private, generated locally in your browser with no upload and no.
Open ToolCSS Text Decoration Generator
Use this free CSS text decoration generator in your browser to build underline overline and strike decoration CSS. Output stays private and local.
Open ToolCSS Text Emphasis
Generate CSS text-emphasis marks for short East Asian or editorial callouts. Free and private in your browser, with nothing uploaded and no account.
Open ToolCSS Text Wrap Balance
Asks the browser to distribute short text across lines more evenly, which is especially useful for headings and narrow cards. Free and private in your browser.
Open ToolCSS Theme Switcher
Build CSS theme switcher in your browser with a live preview and one-click copy. It runs entirely client-side, so nothing is uploaded and no account is needed.
Open ToolCSS Ticket Card
Build CSS ticket card in your browser with a live preview and one-click copy. Free and private: everything is generated locally in your browser with no upload.
Open ToolCSS Typewriter CSS Generator
Generate CSS typewriter CSS in your browser with a live preview and one-click copy — free and private, generated locally in your browser with no upload and no.
Open ToolCSS Variable Fallback
Build nested CSS variable fallback chains for theme tokens with a live preview and one-click copy. Free and private in your browser, with nothing uploaded.
Open ToolCSV To JSON Schema Inferencer
Build CSV to JSON schema inferencer in your browser with a live preview and one-click copy — free and private, generated locally in your browser with no.
Open Toolcu foot to cu meter Converter
Free cu foot to cu meter converter with exact volume math, reverse conversion, copy-ready output, and a quick reference table in your browser.
Open ToolCycling Power Energy Calculator
Calculate work done in kilojoules from average power and duration. Everything is calculated locally in your browser, with no uploads or sign-ups.
Open ToolDew Point Calculator
Free dew point calculator: find the dew point from temperature and relative humidity with the Magnus formula, in your browser.
Open ToolDistance Between Two Points
Free distance calculator for two points on a plane: enter coordinates to get the straight-line distance and the horizontal and vertical gaps in your browser.
Open ToolDocker ENV File
Build .env-style key value rows for Docker Compose examples and local services. Free and private in your browser, with nothing uploaded and no account.
Open ToolEffective Annual Rate Calculator
Free effective annual rate calculator: convert a nominal APR with compounding into the true annual rate, in your browser.
Open ToolEmail Subject Preview
Preview email subject in your browser with a live preview and one-click copy. Free and private: everything is generated locally in your browser with no upload.
Open ToolENV File Diff Viewer
Build env file diff viewer in your browser with a live preview and one-click copy — free and private, generated locally in your browser with no upload and no.
Open ToolEnvironment Variable Example
Work with environment variable example in your browser with a live preview and one-click copy — free and private, generated locally in your browser with no.
Open ToolEquity Dilution Calculator
Calculate founder ownership after issuing new shares or options from current and new share counts. It runs locally in your browser with no uploads.
Open ToolExpense Ratio Drag Calculator
Estimate annual fund fee drag and long-term cost from balance, expense ratio, and years. It runs entirely in your browser — no uploads or accounts.
Open ToolFat Macro Gram Calculator
Calculate grams of fat from fat calories. Every value is computed locally in your browser, so nothing is uploaded, stored, or shared, and no account is needed.
Open ToolFFMI Calculator
Free FFMI calculator: work out your fat-free mass index and normalized value from weight, height, and body fat, in your browser.
Open ToolForce Converter
Free force converter: convert between newtons, kilonewtons, kilogram-force, pound-force, and dyne, in your browser.
Open ToolGeometric Sequence Calculator
Free geometric sequence calculator: find the nth term and sum from the first term and common ratio, computed in your browser.
Open ToolGPA Calculator
Free GPA calculator: find your grade point average from course grades and credits on the 4.0 scale, in your browser.
Open ToolGPA Quality Points Calculator
Calculate quality points from grade points and credit hours. Everything is computed locally in your browser, with no uploads and no sign-ups.
Open ToolGradient Accessibility Checker
Check gradient accessibility in your browser with a live preview and one-click copy — free and private, generated locally in your browser with no upload and.
Open ToolGraphql Query Prettifier
Format GraphQL query in your browser with a live preview and one-click copy. Free and private: everything is generated locally in your browser with no upload.
Open ToolGross Revenue Retention Calculator
Calculate retained MRR, churned MRR, and the GRR percentage from churn. Everything is calculated locally in your browser, with no uploads or sign-ups.
Open ToolHarmonic Mean Calculator
Free harmonic mean calculator: find the harmonic mean of a set of numbers, computed locally in your browser.
Open ToolHarvard Citation Generator
Free Harvard citation generator formats initials, year, title, publisher, and URL fields. Runs in your browser; no uploads or accounts are used.
Open ToolHeat Conduction Calculator
Calculate steady one-dimensional heat conduction rate through a flat layer from conductivity, area, thickness, and temperature gap in your browser.
Open Toolhectare to sq kilometer Converter
Free hectare to sq kilometer converter with exact area math, reverse conversion, copy-ready output, and a quick reference table in your browser.
Open ToolHEX to CMYK Converter
Convert three- or six-digit HEX colors to calculated CMYK percentages, preview the source color, and copy values in your browser without uploads or profiles.
Open ToolHex to HSL Converter
Free hex to HSL converter: turn a hex color into HSL and RGB values, computed locally in your browser.
Open ToolHex to RGBA Converter
Free hex to RGBA converter: turn a hex color and opacity into a CSS rgba() value, computed in your browser.
Open ToolHTML Anchor Tag
Build HTML anchor tags with href, target, rel, and accessible link text with a live preview and one-click copy. Free and private — nothing is uploaded.
Open ToolHTML Id Duplicate Checker
Find duplicate id attributes in pasted HTML and list the repeated values. Everything runs locally in your browser with nothing uploaded and no account needed.
Open ToolHTML to Markdown Converter
Free HTML to Markdown converter that parses a node tree and handles headings, links, lists, emphasis, code, images, quotes, and rules in your browser.
Open ToolImage Padding Adder
Use this free image padding adder in your browser to add transparent or colored padding around a local image. Output stays private and local.
Open ToolIP Address Extractor
Free IP address extractor validates and lists IPv4 plus compressed or full IPv6 addresses from text. Runs in your browser; no uploads or accounts are used.
Open ToolJSON Array Filter Builder
Build JSON array filter in your browser with a live preview and one-click copy. It runs entirely client-side, so nothing is uploaded and no account is needed.
Open ToolJSON Array Sort Tool
Convert JSON array sort tool in your browser with a live preview and one-click copy — free and private, generated locally in your browser with no upload and.
Open ToolJSON Lines Inspector
Inspect JSON lines in your browser with a live preview and one-click copy. Free and private: everything is generated locally in your browser with no upload.
Open ToolJSON Patch Builder
Build JSON patch in your browser with a live preview and one-click copy. Free and private: everything is generated locally in your browser with no upload.
Open ToolJSON To Form Fields Builder
Build JSON to form fields in your browser with a live preview and one-click copy. It runs entirely client-side, so nothing is uploaded and no account is needed.
Open ToolJSON to SQL Insert
Free JSON to SQL INSERT converter that handles object arrays, unioned columns, quoted identifiers, escaped text, booleans, and null in your browser.
Open ToolKilograms to Pounds Converter
Convert kilograms to pounds and pounds to kilograms using the international avoirdupois factor, with precise results calculated in your browser.
Open ToolLink List HTML
Convert link list HTML in your browser with a live preview and one-click copy. Free and private: everything is generated locally in your browser with no upload.
Open ToolMarkdown Callout
Work with markdown callout in your browser with a live preview and one-click copy — free and private, generated locally in your browser with no upload and no.
Open ToolMatrix Multiplication
Free matrix multiplication calculator that parses two matrices, checks compatible dimensions, and computes every row-column product in your browser.
Open Toolmeter/second to mile/hour Converter
Free meter/second to mile/hour converter with exact speed math, reverse conversion, copy-ready output, and a quick reference table in your browser.
Open ToolMiles to Feet Converter
Convert miles to feet and feet to miles with the exact 5,280-foot definition, reverse conversion, and a quick reference table in your browser.
Open ToolMillimeters to Inches Converter
Convert millimeters to inches and inches to millimeters with precise results and a practical reference table, calculated privately in your browser.
Open ToolMMHG to KPA Converter
Convert millimeters of mercury to kilopascals and back using the standard pressure factor, with precise results and a quick table in your browser.
Open ToolMusical Note Duration Calculator
Free musical note duration calculator for a focused result. It converts BPM and note length into milliseconds with private local processing in your browser.
Open ToolNeumorphism Generator
Free neumorphism CSS generator: create soft-UI shadow effects with copyable CSS and a live preview, in your browser.
Open ToolNPM Package Name Validator
Checks lowercase letters, URL-safe characters, length, scoped package format, leading dots or underscores, spaces, and common Node core module names.
Open ToolOKLCH Palette Generator
Generate OKLCH palette in your browser with a live preview and one-click copy. Free and private: everything is generated locally in your browser with no upload.
Open ToolOpen Graph Image Meta
Build open graph image meta in your browser with a live preview and one-click copy — free and private, generated locally in your browser with no upload and no.
Open ToolPackage JSON Dependency Table
Turn package.json dependency blocks into a Markdown table of package names and versions. Free and private in your browser, with nothing uploaded and no account.
Open ToolPackage JSON Scripts Audit
Lists every script and flags common lifecycle hooks such as preinstall, postinstall, prepare, prepublishOnly, and commands containing deploy keywords.
Open ToolPan Area Scale Calculator
Calculate scaled batter weight from a new and old pan area. Everything is computed locally in your browser, with no uploads and no sign-ups.
Open ToolPayroll Burden Calculator
Calculate the burden cost and fully loaded payroll from base pay and a burden rate. It runs entirely in your browser — no uploads or accounts.
Open ToolPercent Composition Calculator
Free percent composition calculator: find each element’s mass percent in a compound, computed in your browser.
Open ToolPerfect Number Checker
Free perfect number checker that lists proper divisors, adds them, and tests whether their sum equals the positive integer privately in your browser.
Open ToolPicture Srcset Generator
Free picture srcset generator that groups responsive image candidates by MIME type and media rule into escaped HTML with valid markup in your browser.
Open ToolPolybius Square Cipher
Free polybius square cipher for a focused result. It encodes letters as row-column digit pairs and decodes them with private local processing in your browser.
Open ToolPressure Calculator
Free pressure calculator: find pressure from force and area, in pascals, kPa, and psi, in your browser.
Open ToolPythagorean Theorem Calculator
Free Pythagorean theorem calculator: enter any two sides of a right triangle to solve the third using a² + b² = c², in your browser.
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