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.
Image Edge Detector
Use this free image edge detector in your browser to apply a Sobel edge detector to local raster luminance. Output stays private and local. No upload is needed.
Open ToolImage Emboss Filter
Use this free image emboss filter in your browser to apply a directional emboss convolution to local raster pixels. Output stays private and local.
Open ToolImage Flipper
Free image flipper: mirror a photo horizontally or vertically and download it, all in your browser.
Open ToolImage Format Converter
Free image format converter that exports uploaded images as PNG, JPEG, or WebP in your browser with preview, format notes, and no server-side processing.
Open ToolImage Hue Rotation Tool
Use this free image hue rotation tool in your browser to rotate local raster hue values while preserving saturation and. Output stays private and local.
Open ToolImage Metadata Viewer
Free image metadata viewer that reads file name, type, size, dimensions, and last modified time locally without uploading your image anywhere.
Open ToolImage Opacity Adjuster
Use this free image opacity adjuster in your browser to multiply local image alpha values by an adjustable opacity. Output stays private and local.
Open ToolImage RGB Channel Splitter
Use this free image RGB channel splitter in your browser to render red green and blue channel panels from one local image. Output stays private and local.
Open ToolImage Sharpen Tool
Use this free image sharpen tool in your browser to apply an adjustable convolution sharpen kernel to local pixels. Output stays private and local.
Open ToolImage Threshold Tool
Use this free image threshold tool in your browser to turn raster pixels black or white at an adjustable luminance threshold. Output stays private and local.
Open ToolImage to Grayscale Converter
Free image to grayscale converter: turn any photo black and white and download it, all in your browser.
Open ToolImage Vignette Tool
Use this free image vignette tool in your browser to darken local image edges with an adjustable radial vignette. Output stays private and local.
Open Toolinch of mercury to pound/sq inch Converter
Free inch of mercury to pound/sq inch converter with exact pressure math, reverse conversion, copy-ready output, and a quick reference table in your browser.
Open ToolInelastic Collision Calculator
Calculate shared velocity and kinetic energy lost when two objects stick together in a one-dimensional collision privately in your browser safely now.
Open ToolIni Section
Build INI section blocks from names and key-value rows. A local app config can create database host, port, and user keys under one section. In your browser.
Open ToolInsulation R Value Calculator
Calculate total insulation R value from layers, thickness, and R per inch using local browser math. It runs locally in your browser with no uploads.
Open ToolInterest Only Loan Calculator
Calculate an interest-only payment and compare it with amortizing repayment for the same balance. It runs entirely in your browser, with no uploads or accounts.
Open ToolInternal Link Anchor Planner
Free internal link anchor planner that runs locally in your browser.
Open ToolInventory Turnover Calculator
Free inventory turnover calculator: find how many times stock sells through and the days on hand, in your browser.
Open ToolIPv4 to IPv6 Converter
Free IPv4 to IPv6 converter: show the mapped and 6to4 IPv6 forms of any IPv4 address, computed locally in your browser.
Open ToolJob Post Clarity Checker
Review a job post for clarity, responsibilities, requirements, compensation, and application instructions.
Open ToolJob Skills Extractor
Paste a job description and extract likely skills plus repeated keywords using local frequency counts and a built-in skill vocabulary in your browser.
Open ToolJoules to Calories Converter
Convert joules to thermochemical calories and calories to joules using the standard energy factor, with precise results calculated in your browser.
Open ToolJSON Diff
Free JSON diff tool that compares two JSON blobs by path. Find added, removed, and changed values locally.
Open ToolJSON Duplicate Key Checker
Detect repeated keys inside JSON object text before the last value silently wins. Free and private in your browser, with nothing uploaded and no account.
Open ToolJSON Escape Unescape
Free JSON escape and unescape tool for string values. Convert raw text to JSON strings and parse them back locally.
Open ToolJSON Formatter & Validator
Pretty-print, minify, and validate JSON instantly. Private and browser-only.
Open ToolJSON Lines Formatter
Format newline-delimited JSON records into readable one-record-per-line output. Free and private in your browser, with nothing uploaded and no account.
Open ToolJSON Merge Patch Builder
Build JSON merge 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 Path Extractor
Extract values from JSON with simple dot paths and array indexes. Useful for API debugging and quick data inspection. Browser-only.
Open ToolJSON Redactor Tool
Convert JSON redactor tool 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 ToolJSON to Python Pydantic
Free JSON to Python Pydantic generator that safely infers nested BaseModel classes, aliases, lists, and field types from data in your browser.
Open ToolJSON to Python TypedDict
Free JSON to Python TypedDict generator that safely infers nested dictionary declarations, list members, and annotations locally in your browser.
Open ToolJSON to Swift Codable
Free JSON to Swift Codable generator that safely infers nested structs, arrays, scalar properties, and CodingKeys aliases locally in your browser.
Open ToolJSON to Yup Schema
Free JSON to Yup schema generator that infers required nested objects, arrays, scalar fields, integers, and nullable values in your browser.
Open ToolJSON Unflattener
Free JSON unflattener that rebuilds nested objects from dot-notation keys. Paste flat JSON and restore structure locally in your browser with preview.
Open ToolJSONL JSON Array Converter
Free JSONL and JSON array converter for line-delimited records. Convert logs and exports locally in your browser.
Open ToolJWT Decoder
Decode JSON Web Token headers and payloads locally in your browser. Inspect claims, expiry, issuer, and audience without upload.
Open ToolKelly Criterion Calculator
Free kelly criterion calculator with labeled inputs and an immediate result. It estimates the full-Kelly bankroll fraction privately in your browser.
Open ToolKelvin to RGB
Free color temperature converter: turn a Kelvin value into an approximate RGB and hex color, from warm candlelight to cool daylight, in your browser.
Open ToolKeyboard Tester
Test keyboard keys in your browser with an on-screen layout, live key highlighting, code logging, reset control, and a local session counter.
Open Toolkilohertz to megahertz Converter
Free kilohertz to megahertz converter with exact frequency math, reverse conversion, copy-ready output, and a quick reference table in your browser.
Open Toolkilojoule to kilocalorie Converter
Free kilojoule to kilocalorie converter with exact energy math, reverse conversion, copy-ready output, and a quick reference table in your browser.
Open Toolkilometer to nautical mile Converter
Free kilometer to nautical mile converter with exact length math, reverse conversion, copy-ready output, and a quick reference table in your browser.
Open Toolkilowatt to BTU/hour Converter
Free kilowatt to btu/hour converter with exact power math, reverse conversion, copy-ready output, and a quick reference table in your browser.
Open ToolLadder Angle Calculator
Free ladder angle calculator with labeled inputs and an immediate result. It checks ladder angle from rise and base distance privately in your browser.
Open ToolLate Fee Percent Calculator
Calculate a late fee and the new balance due from an invoice and a fee rate. Everything is calculated locally in your browser, with no uploads or sign-ups.
Open ToolLaunch Checklist Generator
Generate a practical launch checklist for websites, campaigns, tools, and product updates.
Open Toolleague to kilometer Converter
Free league to kilometer converter with exact length math, reverse conversion, copy-ready output, and a quick reference table in your browser.
Open ToolLexical Diversity Calculator
Free lexical diversity calculator reports unique word types, tokens, and type-token ratio. Runs in your browser; no uploads or accounts are used.
Open ToolLine Sorter
Alphabetize lines in a pasted list.
Open ToolLinear Regression Calculator
Free linear regression calculator: fit a least-squares line to your x,y points and get slope, intercept, and R-squared, in your browser.
Open ToolLinear Thermal Expansion Calculator
Free linear thermal expansion calculator with an immediate result. It estimates length change from temperature change privately in your browser.
Open ToolLines to JSON Array
Free tool to convert text lines into a JSON array of strings, with trim and skip-empty options, in your browser.
Open ToolLink Tag Preload
Work with link tag preload 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 Toollink to meter Converter
Free link to meter converter with exact factors, reverse conversion, copy-ready output, and a quick reference table that runs in your browser.
Open ToolLinkedIn About Builder
Build a LinkedIn About section from current role, years of experience, top skills, signature achievement, and current career goal in your browser.
Open ToolLinkedIn Post Formatter
Free LinkedIn post formatter that turns rough notes into a hook, spaced body, takeaway, and call-to-action structure. Runs locally in your browser for...
Open ToolList Shuffler
Free list shuffler for cleaning, transforming, and checking pasted text. Process content locally in your browser without uploads.
Open ToolLLMs.txt Generator
Create a starter llms.txt file for AI systems and content guidance.
Open ToolLoan Comparison Calculator
Compare two fixed loans by payment, total interest, and lifetime cost using manual rates and terms. It runs locally in your browser with no uploads.
Open ToolLottery Odds Calculator
Free lottery odds calculator: find the odds of matching all numbers in a pick-k-from-n lottery, in your browser.
Open ToolLTV:CAC Ratio Calculator
Free LTV:CAC ratio calculator that compares customer lifetime value, acquisition cost, and payback health signals. Runs locally in your browser for private...
Open ToolMach to MPH Converter
Free mach to mph converter. It converts Mach values to miles per hour using a stated speed of sound and keeps entered data private in your browser.
Open ToolMacros to Calories Calculator
Free macros to calories calculator: turn protein, carbs, and fat grams into calories and percentages, in your browser.
Open ToolMarkdown Badge Row
Work with markdown badge row in your browser with a live preview and one-click copy — free and private, generated locally in your browser with no upload and.
Open ToolMarkdown Frontmatter Table
Work with markdown frontmatter table in your browser with a live preview and one-click copy — free and private, generated locally in your browser with no.
Open ToolMarkdown Heading Anchor
Preview GitHub-style anchors generated from Markdown headings with a live preview and one-click copy. Free and private in your browser, with nothing uploaded.
Open ToolMarkdown to HTML Converter
Convert common Markdown headings, lists, links, bold, italic, code, and paragraphs into escaped HTML locally.
Open ToolMatrix Transpose Calculator
Free matrix transpose calculator that swaps rows and columns for any rectangular numeric matrix and shows the new dimensions in your browser.
Open ToolMedian Absolute Deviation
Free median absolute deviation calculator that finds the median, absolute residuals, and robust MAD for pasted numeric data in your browser.
Open ToolMeeting Agenda Builder
Build a clear meeting agenda with goals, topics, timing, attendees, and next steps. Free private browser tool.
Open ToolMeeting Time Planner
Free meeting time planner that calculates dates and times locally in your browser with specific examples, limits, and copy-ready output. No account required.
Open Toolmegabit to megabyte Converter
Free megabit to megabyte converter with exact data math, reverse conversion, copy-ready output, and a quick reference table in your browser.
Open Toolmegapascal to pound/sq inch Converter
Free megapascal to pound/sq inch converter with exact pressure math, reverse conversion, copy-ready output, and a quick reference table in your browser.
Open ToolMeta Description Length Checker
Write and check meta descriptions for concise search snippets.
Open ToolMeta Viewport Auditor
Inspect a viewport meta tag for width, initial-scale, and zoom-limiting values. Free and private in your browser, with nothing uploaded and no account.
Open ToolMeters to Feet Converter
Convert meters to feet and feet to meters using the international foot definition, with six-significant-figure results calculated in your browser.
Open ToolMidpoint Calculator (Geographic)
Free geographic midpoint calculator: find the great-circle midpoint between two coordinates, computed in your browser.
Open ToolMileage Calculator for Reimbursement
Free mileage calculator for reimbursement: multiply your business miles by the rate per mile you enter to get the amount owed, privately in your browser.
Open ToolMilestone Payment Calculator
Calculate a milestone payment and the remaining balance from a project total. Everything is calculated locally in your browser, with no uploads or sign-ups.
Open ToolMilitary Time Converter
Free military time converter: switch between 12-hour and 24-hour clock formats, computed locally in your browser.
Open Toolminute to hour Converter
Free minute to hour converter with exact factors, reverse conversion, copy-ready output, and a quick reference table that runs in your browser.
Open ToolMobility Session Time Calculator
Calculate session length from an exercise count and minutes each. Everything is computed locally in your browser, with no uploads and no sign-ups.
Open ToolModular Inverse Calculator
Free modular inverse calculator that finds an integer inverse modulo m, with labeled assumptions and an immediate result calculated privately in your browser.
Open ToolMonthly Retainer Calculator
Estimate a monthly service retainer from hours, hourly value, overhead, margin, and tool costs. Free private browser tool.
Open ToolMyszkowski Transposition Cipher
Free Myszkowski transposition cipher handles repeated keyword letters as shared rank groups. Runs in your browser; no uploads or accounts are used.
Open Toolnanometer to micron Converter
Free nanometer to micron converter with exact length math, reverse conversion, copy-ready output, and a quick reference table in your browser.
Open ToolNATO Phonetic Alphabet Converter
Free NATO phonetic alphabet converter: spell out text as Alpha, Bravo, Charlie for clear speech, in your browser.
Open ToolNATO Phonetic Converter
Free nato phonetic converter for cleaning, transforming, and checking pasted text. Process content locally in your browser without uploads.
Open ToolNet Profit Margin Calculator
Free net profit margin calculator: find the percentage of revenue kept as profit after all costs, in your browser.
Open ToolNet Revenue Retention Calculator
Calculate ending MRR and net revenue retention from a starting MRR and net expansion. It runs entirely in your browser — no uploads or accounts.
Open ToolNet Worth Tracker
Free net worth tracker that totals pasted assets and liabilities to estimate current net worth locally. Runs locally in your browser for private planning.
Open ToolNetlify Redirects
Generate Netlify _redirects rules from source path, target path, and status code. A moved docs page can map /old-guide to /new-guide with a 301 status.
Open ToolNewsArticle Schema Generator
Generate NewsArticle JSON-LD from headline, author, dates, image, and publisher fields, then copy the structured data in your browser without uploads.
Open ToolNewsletter Outline Generator
Generate a simple newsletter outline from a topic, audience, and supporting notes.
Open ToolNewsletter Preview Builder
Free newsletter preview builder that runs locally in your browser.
Open ToolNext Birthday Countdown
Free next birthday countdown: find how many days until your next birthday and the age you will turn, in your browser.
Open ToolNormal Distribution Calculator
Free normal distribution calculator returning z score, density, lower cumulative probability, and upper tail for x, mean, and SD in your browser.
Open ToolNormal Distribution CDF
Free normal distribution cdf with labeled inputs and an immediate result. It estimates cumulative normal probability below x privately in your browser.
Open ToolNote Frequency Reference
Free musical note frequency tool: find the exact frequency of any note and play it, in your browser.
Open ToolNPM Engines Field Builder
The engines field documents the runtime versions a package expects, such as Node 20 or newer. Free and private in your browser, with nothing uploaded.
Open ToolNPS Survey Builder
Free NPS survey builder that creates 0-10 question copy, follow-up prompts, segments, and response handling notes. Runs locally in your browser for private...
Open ToolNPV Calculator
Free net present value calculator: discount a series of cash flows to today at a chosen rate to judge an investment, computed in your browser.
Open ToolNth Weekday of Month Calculator
Free nth weekday calculator: find the date of, say, the third Monday of a month, computed in your browser.
Open ToolNumber Formatter
Free number formatter: add thousands separators and set decimal places for any number, in your browser.
Open ToolNumber Memory Test
Play a number memory test that adds one digit after each correct answer, hides the number, tracks your level, and saves your best locally in this browser.
Open ToolNumber to Ordinal Converter
Free number to ordinal converter: turn numbers into their ordinal form like 1st, 2nd, 3rd, computed in your browser.
Open ToolOG Image Generator
Free Open Graph image generator: create a 1200×630 social share image with a title, downloadable as PNG, in your browser.
Open ToolOG Image Maker
Free OG image maker for composing a 1200 by 630 social preview card in canvas with title, subtitle, colors, and downloadable PNG export locally.
Open Tooloil barrel to US gallon Converter
Free oil barrel to us gallon converter with exact volume math, reverse conversion, copy-ready output, and a quick reference table in your browser.
Open ToolOKLCH Gradient Generator
Generate OKLCH gradient 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 ToolOnboarding Plan Generator
Generate a 30-day onboarding plan for a new hire, contractor, or team member.
Open ToolOne-Sample Mean Z-Test
Free one-sample mean z-test calculator using sample mean, hypothesized mean, known population deviation, and n with p value in your browser.
Open ToolOnline Metronome
Free online metronome: keep time with an adjustable tempo and accented beats, in your browser.
Open ToolOpen Graph Tag Generator
Create OG and Twitter/X meta tags for social sharing previews.
Open ToolOrdinal Number to Word Converter
Free ordinal number to word converter spells whole-number positions such as forty-second. Runs in your browser; no uploads or accounts are used.
Open ToolOutlier Detector
Free outlier detector: flag outliers in a data set using the 1.5 IQR rule, computed locally in your browser.
Open ToolPace Band Calculator
Calculate pace per mile and 5K split targets from race distance and goal time inputs. It runs entirely in your browser — no uploads or accounts.
Open ToolPalette Harmony
Generate palette harmony 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 ToolPalindrome Checker
Free palindrome checker for cleaning, transforming, and checking pasted text. Process content locally in your browser without uploads.
Open ToolParagraph Simplifier
Simplify a dense paragraph with local readability rules, shorter sentences, and complex-word flags. Private browser-only utility.
Open ToolParity Bit Calculator
Free parity bit calculator: find the even and odd parity bits for a run of bits, computed locally in your browser.
Open Toolparsec to light-year Converter
Free parsec to light-year converter with exact length math, reverse conversion, copy-ready output, and a quick reference table in your browser.
Open Toolpascal to pound/sq inch Converter
Free pascal to pound/sq inch converter with exact pressure math, reverse conversion, copy-ready output, and a quick reference table in your browser.
Open ToolPassword Strength Meter
Free password strength meter: estimate entropy in bits, rate strength, and get specific feedback — all locally in your browser with nothing stored.
Open ToolPDF to Text
Extract the selectable text from a PDF in your browser and copy or download it as plain text. Your document is never uploaded to any server.
Open Toolpennyweight to gram Converter
Free pennyweight to gram converter with exact mass math, reverse conversion, copy-ready output, and a quick reference table in your browser.
Open ToolPercent Off Calculator
Free percent off calculator: find the sale price and how much you save from an original price and a percentage off, in your browser.
Open ToolPercentage Change Calculator
Free percentage change calculator that compares before and after values with increase, decrease, and absolute difference. Runs locally in your browser for...
Open ToolPercentile Rank Calculator
Free percentile rank calculator with labeled inputs and an immediate result. It finds rank from counts below and equal privately in your browser.
Open ToolPixels to Points Converter
Convert CSS pixels to typographic points and points to pixels using the standard 96-DPI relationship, with clear, precise results in your browser.
Open ToolPizza Dough Ball Calculator
Calculate the weight of each dough ball from total dough and a ball count. Everything is calculated locally in your browser, with no uploads or sign-ups.
Open ToolPolygon Area Calculator
Free polygon area calculator using the shoelace formula on ordered coordinate pairs, with signed orientation and absolute area in your browser.
Open ToolPomodoro Timer
Free pomodoro timer that calculates dates and times locally in your browser with specific examples, limits, and copy-ready output. No account required.
Open ToolPort Number Lookup
Free port number lookup: search common TCP and UDP ports by number or service name, all in your browser.
Open ToolPotential Energy Calculator
Free gravitational potential energy calculator: find stored energy from mass, gravity, and height with PE = mgh, in your browser.
Open Toolpound to ounce Converter
Free pound to ounce converter with exact factors, reverse conversion, copy-ready output, and a quick reference table that runs in your browser.
Open ToolPower Converter
Free power converter that converts values instantly in your browser. Includes examples, formulas, limits, copy-ready output, and local privacy.
Open ToolPrice Per Square Foot Calculator
Free price per square foot calculator: find the price per square foot from a total price and area, in your browser.
Open ToolProbability Calculator
Free probability calculator: find the probability of an event from favorable and total outcomes, in your browser.
Open ToolProduct Requirements Checklist
Generate a practical product requirements checklist for new features, pages, tools, and internal systems.
Open ToolProject Handoff Checklist
Create a handoff checklist for delivering files, access, documentation, and next steps.
Open ToolProjectile Motion Calculator
Free projectile motion calculator: find range, maximum height, and flight time from launch speed and angle, in your browser.
Open ToolProjectile with Height Calculator
Calculate projectile flight time, range, and peak height from launch speed, angle, and starting elevation with private results in your browser.
Open ToolProportion Solver
Free proportion solver: solve a/b = c/d for the missing value by cross-multiplication, in your browser.
Open ToolProtein Per Meal Calculator
Calculate protein per meal from a daily target and a meal count. Everything is computed locally in your browser, with no uploads and no sign-ups.
Open ToolPunycode IDN Converter
Convert internationalized domain labels to ASCII Punycode and decode xn-- labels to Unicode using the RFC 3492 algorithm in your browser safely now.
Open ToolPX to REM Converter
Free px to rem converter: switch between pixels and rem units at any root font size, in your browser.
Open ToolQuarter Fiscal Date Helper
Free quarter fiscal date helper that calculates dates and times locally in your browser with specific examples, limits, and copy-ready output.
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