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.
Heat Index Calculator
Free heat index calculator: find the feels-like temperature from heat and humidity using the NWS formula, in your browser.
Open Toolhectopascal to inch of mercury Converter
Free hectopascal to inch of mercury converter with exact pressure math, reverse conversion, copy-ready output, and a quick reference table in your browser.
Open Toolhertz to kilohertz Converter
Free hertz to kilohertz converter with exact frequency math, reverse conversion, copy-ready output, and a quick reference table in your browser.
Open ToolHexagon Area Calculator
Free regular hexagon area calculator: find the area and perimeter from the side length, in your browser.
Open ToolHomophonic Substitution Cipher
Free homophonic substitution cipher alternates two numeric symbols for each plaintext letter. Runs in your browser; no uploads or accounts are used.
Open ToolHorsepower to Kilowatts Converter
Convert mechanical horsepower to kilowatts and kilowatts to horsepower using the standard power factor, with precise results in your browser.
Open Toolhour to day Converter
Free hour to day converter with exact factors, reverse conversion, copy-ready output, and a quick reference table that runs in your browser.
Open ToolHourly to Salary Calculator
Convert an hourly rate into weekly, monthly, and annual pay from hours and weeks entered. It runs entirely in your browser — no uploads or accounts.
Open ToolHSV ↔ RGB Converter
Free HSV and RGB converter: switch a color between hue-saturation-value and RGB or hex, computed locally in your browser.
Open ToolHtaccess Redirect Generator
Free htaccess redirect generator that parses source and destination pairs into Apache Redirect or RewriteRule lines with clear errors in your browser.
Open ToolHTML Description List
Build semantic HTML description lists from term and definition rows. A glossary can turn API Key and Access Token definitions into dl, dt, and dd markup.
Open ToolHTML Email Button
Generate table-based HTML email buttons with URL, label, padding, and colors. Free and private in your browser, with nothing uploaded and no account.
Open ToolHTML Entity Encoder Decoder
Encode and decode common HTML entities for pasted snippets and docs examples. Free and private in your browser, with nothing uploaded and no account.
Open ToolHTML Entity Roundtrip Tool
Build HTML entity roundtrip tool in your browser with a live preview and one-click copy — free and private, generated locally in your browser with no upload.
Open ToolHTML Form Action
Build form method, action, enctype, and target snippets for HTML forms with a live preview and one-click copy. Free and private — nothing is uploaded.
Open ToolHTML Landmark Outline
Detects common landmark elements such as main, nav, header, footer, aside, section with labels, and elements with landmark roles. Private, in your browser.
Open ToolHTML Responsive Image Audit
Checks for alt, width, height, srcset, sizes, loading, and decoding because those affect accessibility, layout stability, and loading behavior.
Open ToolHTML Tag Stripper
Free html tag stripper that runs locally in your browser.
Open ToolHttp Cache Control
Build HTTP cache control 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 ToolHTTP Header Reference
Free HTTP header reference with searchable meanings for common request, response, cache, and security headers.
Open ToolHWB Color Converter
Use this free HWB color converter in your browser to convert sRGB hex colors to CSS HWB and back. Output stays private and local. No upload is needed.
Open ToolIBAN Validator
Free IBAN validator: check an international bank account number against the ISO mod-97 checksum and see its country and length, locally in your browser.
Open ToolIdeal Gas Law Calculator
Free ideal gas law calculator: enter any three of pressure, volume, moles, and temperature to solve for the fourth using PV = nRT, in your browser.
Open ToolIEEE Citation Generator
Free IEEE citation generator creates numbered author, title, publisher, year, and URL entries. Runs in your browser; no uploads or accounts are used.
Open ToolImage Blur Tool
Use this free image blur tool in your browser to apply a downloadable box blur to local raster pixels. Output stays private and local. No upload is needed.
Open ToolImage Border Adder
Use this free image border adder in your browser to draw a configurable solid border around a local image. Output stays private and local. No upload is needed.
Open ToolImage Cropper
Free image cropper that crops uploaded images by pixel coordinates in your browser, with live preview, exact rectangle controls, and downloadable PNG output.
Open ToolImage Gamma Correction
Use this free image gamma correction in your browser to apply gamma correction directly to local RGB channels. Output stays private and local.
Open ToolImage Pixelate Tool
Use this free image pixelate tool in your browser to downsample and nearest-neighbor upscale local raster pixels. Output stays private and local.
Open ToolImage Posterize Tool
Use this free image posterize tool in your browser to reduce local RGB channels to a selected number of tonal levels. Output stays private and local.
Open ToolImage Rotator
Free image rotator: rotate a photo by 90, 180, or 270 degrees and download it, all in your browser.
Open ToolImage Saturation Adjuster
Use this free image saturation adjuster in your browser to change raster saturation with luminance-preserving pixel math. Output stays private and local.
Open ToolImage Solarize Tool
Use this free image solarize tool in your browser to invert local channel values above an adjustable threshold. Output stays private and local.
Open ToolImage Tint Overlay
Use this free image tint overlay in your browser to blend a chosen tint color into every local image pixel. Output stays private and local. No upload is needed.
Open ToolImpulse and Momentum Calculator
Calculate impulse, final momentum, and velocity change from constant force, duration, initial momentum, and mass privately in your browser safely now.
Open ToolInclined Plane Calculator
Calculate normal force, kinetic friction, and acceleration for a mass on an inclined plane using angle and friction inputs in your browser safely now.
Open ToolInflation Calculator
Free inflation calculator: see how prices and purchasing power change over time at a given rate, in your browser.
Open ToolInitials Extractor
Free initials extractor for cleaning, transforming, and checking pasted text. Process content locally in your browser without uploads.
Open ToolInitiative Average Calculator
Calculate the average initiative bonus from a total and a character count. Everything is calculated locally in your browser, with no uploads or sign-ups.
Open ToolInvisible Text Generator
Free invisible text generator: create blank, invisible characters to copy for empty messages and usernames, in your browser.
Open ToolInvoice Tax Add Calculator
Calculate the tax and tax-inclusive total from a subtotal and a tax rate. Everything is calculated locally in your browser, with no uploads or sign-ups.
Open ToolInvoice Tax Remove Calculator
Calculate the pre-tax subtotal and tax portion from a tax-inclusive total. Everything is calculated locally in your browser, with no uploads or sign-ups.
Open ToolIPv6 Compressor
Free IPv6 compressor that validates eight hextets, expands double-colon input, removes leading zeros, and compresses the longest zero run in your browser.
Open ToolIPv6 Expander
Free IPv6 tool: expand a compressed address to its full eight-group form, or compress a full address to its shortest valid form, in your browser.
Open ToolIsogram Checker
Free isogram checker: test whether a word has no repeated letters and see which letters repeat, computed locally in your browser.
Open ToolJs Import Sort
Group and sort JavaScript import lines for quick cleanup before formatting. Everything runs locally in your browser with nothing uploaded and no account needed.
Open ToolJSON Array Group By Tool
Convert JSON array group by tool in your browser with a live preview and one-click copy — free and private, generated locally in your browser with no upload.
Open ToolJSON Diff Visualizer
Visualize JSON diff 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 Flatten Preview Tree
Convert JSON flatten preview tree in your browser with a live preview and one-click copy — free and private, generated locally in your browser with no upload.
Open ToolJSON Key Counter
Free JSON key counter: count keys, values, and nesting depth of a JSON document, computed in your browser.
Open ToolJSON Key Path Extractor
Extract JSON key path 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 Merge
Free JSON merge tool that deep-merges two objects and shows the combined result. Choose whether arrays replace or concatenate locally with preview.
Open ToolJSON Path Picker
Pick nested JSON paths from pasted objects and list dot-path style references. Free and private in your browser, with nothing uploaded and no account.
Open ToolJSON Pointer Tester
Test JSON pointer 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 String Escaper
Free JSON string escaper: escape text into a JSON string literal or unescape one back to raw text, in your browser.
Open ToolJSON to C Sharp Class
Free JSON to C Sharp class generator that infers nested models, System.Text.Json attributes, lists, and value types with clear output in your browser.
Open ToolJSON to INI Converter
Free JSON to INI converter that safely writes root settings, named sections, dotted nested keys, arrays, and safely quoted values in your browser.
Open ToolJSON to Java Class
Free JSON to Java class generator that safely infers nested POJOs, Jackson property annotations, lists, and scalar field types in your browser.
Open ToolJSON to Kotlin Data Class
Free JSON to Kotlin data class generator that infers nested serializable models, lists, scalar types, and key aliases with clear output in your browser.
Open ToolJSON to Markdown List
Free JSON to Markdown list converter that renders nested objects and arrays as readable bullet lists. Document API samples locally in seconds.
Open ToolJSON to Mongoose Schema
Free JSON to Mongoose schema generator that infers required nested definitions, arrays, strings, numbers, and booleans with valid syntax in your browser.
Open ToolJSON to PHP Class
Free JSON to PHP class generator that infers typed readonly constructor properties and nested value objects with strict types in your browser.
Open ToolJSON to Plist Converter
Free JSON to XML plist converter that safely serializes dictionaries, arrays, strings, numbers, and booleans with escaped values in your browser.
Open ToolJSON to Properties Converter
Free JSON to Java properties converter that safely flattens nested objects and arrays into escaped dotted keys and scalar values in your browser.
Open ToolJSON to Protobuf Message
Free JSON to Protobuf message generator that infers nested messages, repeated fields, scalar types, and stable field numbers in your browser.
Open ToolJSON to Rust Serde Struct
Free json to rust serde struct. It infers a Rust struct with Serde derives from one JSON object and keeps entered data private in your browser.
Open ToolJSON to SQL Table
Free JSON to SQL tool: infer a CREATE TABLE statement with column types from a sample JSON object or array, generated locally in your browser.
Open ToolJSON to TOML Converter
Convert JSON objects to readable TOML tables, scalar values, and arrays, see clear parse errors, and copy the result privately in your browser.
Open ToolJSON To TypeScript Interface
Free JSON to TypeScript interface generator that infers basic field types from sample JSON locally in your browser.
Open ToolJSON To XML Converter
Free JSON to XML converter for simple objects and arrays. Transform sample data into readable XML locally in your browser.
Open ToolJSON to Zod Schema
Free JSON to Zod schema generator that safely infers executable object, array, scalar, integer, and null validators from a sample in your browser.
Open ToolJSON Trailing Comma Finder
Find trailing commas that make JSON invalid and show the line numbers with a live preview and one-click copy. Free and private — nothing is uploaded.
Open ToolJSONL to JSON Array
Free JSON Lines converter: turn newline-delimited JSON objects into a single JSON array, computed locally in your browser.
Open ToolJsonpath
Convert jsonpath 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 ToolJulian Day Number Calculator
Free Julian Day Number calculator: convert a calendar date to its astronomical Julian day, in your browser.
Open ToolJwt Claims Table
Decode JWT payload text into a readable claims table without verifying the signature. Free and private in your browser, with nothing uploaded and no account.
Open ToolKepler's Third Law Calculator
Calculate ideal orbital period from semi-major axis and central mass using Newtonian Kepler form, with seconds and days returned in your browser.
Open ToolKilobytes to Kibibytes Converter
Convert decimal kilobytes to binary kibibytes and kibibytes to kilobytes using exact byte definitions, with precise results in your browser.
Open ToolKilograms to Stone Converter
Convert kilograms to decimal stone and stone to kilograms using the international avoirdupois definition, with precise results in your browser.
Open ToolKilometers to Miles Converter
Convert kilometers to miles and miles to kilometers using the standard international factor, with a practical reference table in your browser.
Open ToolKnots to KM/H Converter
Convert knots to kilometers per hour and back using the exact 1.852-kilometer nautical mile, with a clear, practical speed table in your browser.
Open ToolKnots to MPH Converter
Convert knots to miles per hour and miles per hour to knots using the international nautical mile, with precise speed results in your browser.
Open ToolKPA to PSI Converter
Convert kilopascals to PSI and PSI to kilopascals using the standard pressure factor, with precise results and a reference table in your browser.
Open ToolLab Dilution Factor Calculator
Calculate final concentration and dilution factor from stock and volumes. Everything is calculated locally in your browser, with no uploads or sign-ups.
Open ToolLanding Page Lead Calculator
Estimate leads and non-converting visits from traffic and a conversion rate. Everything is calculated locally in your browser, with no uploads or sign-ups.
Open ToolLanding Page Section Outline
Draft landing page section outline in your browser with a live preview and one-click copy — free and private, generated locally in your browser with no upload.
Open ToolLCH Color Converter
Use this free LCH color converter in your browser to convert sRGB hex colors to CIE LCH and back. Output stays private and local. No upload is needed.
Open ToolLead Time Demand Calculator
Calculate lead-time demand from average daily demand and lead time. Everything is calculated locally in your browser, with no uploads or sign-ups.
Open ToolLean Body Mass Calculator
Free lean body mass calculator using the Boer formula from your weight, height, and sex, computed locally in your browser.
Open ToolLength Converter
Free length converter that converts values instantly in your browser. Includes examples, formulas, limits, copy-ready output, and local privacy.
Open ToolLetter Grade Calculator
Free letter grade calculator: convert a percentage into a letter grade and GPA points, computed in your browser.
Open ToolLink Rel Auditor
Audit link rel tags for canonical, preload, preconnect, stylesheet, and alternate hints. Free and private in your browser, with nothing uploaded and no account.
Open ToolLinkedIn Click Rate Calculator
Estimate clicks and confirm the click-through rate from impressions and a click percentage. It runs entirely in your browser, with no uploads or accounts.
Open Toolliter to oil barrel Converter
Free liter to oil barrel converter with exact volume math, reverse conversion, copy-ready output, and a quick reference table in your browser.
Open ToolLiters to Cubic Feet Converter
Convert liters to cubic feet and cubic feet to liters using the exact international-foot volume relationship, with precise results in your browser.
Open ToolLiters to US Gallons Converter
Convert liters to US gallons and US gallons to liters using the exact US liquid-gallon definition, with a practical reference table in your browser.
Open ToolLoan-to-Value Calculator
Free loan-to-value calculator: find the LTV ratio from your loan amount and property value, in your browser.
Open ToolLocal SEO Checklist Generator
Generate a local SEO checklist for service-area pages, listings, reviews, and local content.
Open ToolLogarithm Calculator
Free logarithm calculator: compute the log of a number in any base, plus natural and base-2 logs, in your browser.
Open ToolLogo Churn Count Calculator
Calculate churned and retained logos from a starting count and a churn rate. Everything is calculated locally in your browser, with no uploads or sign-ups.
Open ToolManifest Web App
Work with manifest web app 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 ToolMargin of Error Calculator
Free margin of error calculator for survey proportions using sample size, expected proportion, and confidence level, entirely in your browser.
Open ToolMarkdown Frontmatter
Preview Markdown frontmatter fields and body content from a pasted document. Free and private in your browser, with nothing uploaded and no account.
Open ToolMarkdown Link Auditor
Audit markdown link 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 Link List Cleaner
Clean pasted Markdown link lists by trimming duplicates and sorting labels. Everything runs locally in your browser with nothing uploaded and no account needed.
Open ToolMarkdown Table Cleaner
Clean up markdown table 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 ToolMarkdown Task List Progress
Count checked and unchecked Markdown task-list items and show completion percent. Free and private in your browser, with nothing uploaded and no account.
Open ToolMarkdown to JSX Converter
Free Markdown to JSX converter that parses headings, paragraphs, lists, quotes, links, emphasis, inline code, and fenced blocks in your browser.
Open ToolMarkup Price Calculator
Free markup price calculator: find the selling price from a cost and markup percentage, in your browser.
Open ToolMass Percent Calculator
Free mass percent calculator: find the mass percent of a solute in a solution, computed in your browser.
Open ToolMass-Energy Calculator (E=mc²)
Free E=mc² calculator: find the energy equivalent of a mass, computed locally in your browser.
Open ToolMaterial Palette Generator
Free Material-style palette generator: turn one color into a 50–900 tonal scale of tints and shades, computed locally in your browser.
Open ToolMaterial You Palette
Generate material you palette in your browser with a live preview and one-click copy — free and private, generated locally in your browser with no upload and.
Open ToolMatrix Inverse Calculator
Free matrix inverse calculator using pivoted Gauss-Jordan elimination for nonsingular square matrices, with clean private output in your browser.
Open ToolMax Heart Rate Calculator
Free maximum heart rate calculator using age-based formulas, computed locally in your browser.
Open ToolMD5 Checksum Explainer
Free MD5 checksum explainer that compares MD5 with modern browser hash options. Learn why SubtleCrypto omits MD5 locally.
Open ToolMD5 Hash Generator
Generate a lowercase MD5 digest from UTF-8 text entirely in your browser, copy the 32-character result, and compare known test vectors without uploads.
Open ToolMean Confidence Interval
Calculate a z-based confidence interval for a sample mean from its standard deviation, sample size, and critical value in your browser without uploads.
Open ToolMeat Roasting Time Calculator
Free roasting time calculator: estimate cooking time by weight for beef, chicken, pork, lamb, and turkey, in your browser.
Open Toolmebibyte to kibibyte Converter
Free mebibyte to kibibyte converter with exact data math, reverse conversion, copy-ready output, and a quick reference table in your browser.
Open ToolMedia Pitch Builder
Free media pitch builder that structures hook, why-now, credibility, story angle, and ask for journalist outreach. Runs locally in your browser for private...
Open ToolMegabytes to Mebibytes Converter
Convert decimal megabytes to binary mebibytes and mebibytes to megabytes using exact byte definitions, with precise results in your browser.
Open Toolmegahertz to gigahertz Converter
Free megahertz to gigahertz converter with exact frequency math, reverse conversion, copy-ready output, and a quick reference table in your browser.
Open ToolMessy CSV Normalizer
Clean pasted CSV-style rows by trimming spaces, lowercasing headers, and removing duplicate lines.
Open ToolMetric Tonnes to US Tons Converter
Convert metric tonnes to US short tons and back using the standard mass relationship, with precise six-significant-figure results in your browser.
Open Toolmil to inch Converter
Free mil to inch converter with exact factors, reverse conversion, copy-ready output, and a quick reference table that runs in your browser.
Open ToolMilligrams to Grams Converter
Convert milligrams to grams and grams to milligrams using exact metric scaling, with six-significant-figure results calculated in your browser.
Open ToolMillimeters to Centimeters
Convert millimeters to centimeters and centimeters to millimeters using exact metric scaling, with precise results and a table in your browser.
Open Toolmillisecond to second Converter
Free millisecond to second converter with exact time math, reverse conversion, copy-ready output, and a quick reference table in your browser.
Open ToolMinimum Payment Payoff Calculator
Estimate payoff months and interest from balance, APR, and fixed monthly payment. Everything is calculated locally in your browser, with no uploads or sign-ups.
Open ToolMLA Citation Generator
Free MLA citation generator formats author, title, publisher, year, and URL fields. It runs in your browser without uploads or external requests.
Open ToolMolar Mass Calculator
Free molar mass calculator: enter a chemical formula to get its molar mass from standard atomic weights, with parentheses supported, in your browser.
Open ToolMolarity Calculator
Free molarity calculator: find solution concentration in moles per litre from moles and volume, in your browser.
Open ToolMoles to Grams Calculator
Free moles to grams calculator: convert moles to mass using molar mass, computed in your browser.
Open ToolMomentum Calculator
Free momentum calculator: find linear momentum from mass and velocity, computed locally in your browser.
Open ToolMonochromatic Palette Generator
Free monochromatic palette generator: build a palette from one hue at different lightness levels, in your browser.
Open Toolmonth to year Converter
Free month to year converter with exact factors, reverse conversion, copy-ready output, and a quick reference table that runs in your browser.
Open ToolMonthly Burn Multiple Calculator
Calculate the burn multiple from net burn and net new ARR. Everything is computed locally in your browser, with no uploads and no sign-ups.
Open ToolMortgage Payment With Escrow
Estimate monthly mortgage principal, interest, property tax, insurance, and PMI from manual assumptions, calculated privately in your browser.
Open ToolMortgage Payoff Accelerator
Free mortgage payoff accelerator that estimates interest saved and months reduced from extra monthly payments. Runs locally in your browser for private...
Open ToolMoving Average Calculator
Free moving average calculator: smooth a series with a simple moving average of any window, in your browser.
Open ToolMPH to KM/H Converter
Convert miles per hour to kilometers per hour and back with the exact international mile factor, precise results, and a quick table in your browser.
Open ToolMRR Calculator
Free monthly recurring revenue calculator: find MRR and ARR from customers and average revenue, in your browser.
Open ToolMulch Bag Count Calculator
Calculate mulch bags from area, depth, bag size, and waste. Everything is computed locally in your browser, with no uploads and no sign-ups.
Open ToolMulch Calculator
Free mulch calculator: find how much mulch you need by area and depth, in cubic yards and bags, computed in your browser.
Open ToolMultinomial Coefficient
Free multinomial coefficient calculator for category counts, showing total factorial over each group factorial with exact output in your browser.
Open ToolN-Gram Generator
Free n-gram generator creates consecutive one-word through five-word windows from pasted text. Runs in your browser; no uploads or accounts are used.
Open ToolNamed CSS Color Finder
Find named CSS color 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 Toolnanosecond to microsecond Converter
Free nanosecond to microsecond converter with exact time math, reverse conversion, copy-ready output, and a quick reference table in your browser.
Open ToolNautical Miles to Kilometers
Convert nautical miles to kilometers and kilometers to nautical miles using the exact 1.852 km definition, with results calculated in your browser.
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