Tools
Small browser utilities that run on your machine, nothing uploaded
Files & Code
42JSON Formatter and Validator — Pretty Print, Minify, Find the Syntax ErrorIndent, minify and validate JSON, with the error lineJSON Diff — Compare Two JSON Documents by Path, Not by LineAdded, removed and changed keys between two JSON documentsYAML to JSON Converter — Both Directions, with Indentation Errors LocatedConvert YAML to JSON and back, in the browserCSV to JSON Converter — RFC 4180 Quoting, Tabs and Semicolons, Both DirectionsCSV or a pasted spreadsheet to JSON, and backJSON to TypeScript — Generate Interfaces from a Sample ResponseInterfaces or type aliases inferred from a JSON sampleAPI Response Viewer — Explore JSON by Path, Type and NullEvery value in a JSON response, with its path and typeQR Code Generator — URL or Text to a Downloadable PNGEncode a link or text as a PNG QR code, offlineHash Generator — SHA-256, SHA-512, SHA-1, MD5 and CRC32 for Text or a FileSix digests of a string or a local file, computed in the pageUUID Generator — Random v4 Identifiers in Bulk, With Format OptionsBatch of random v4 UUIDs from the browser CSPRNGJWT Decoder — Read the Header and Claims of a JSON Web TokenBase64url-decode a token and read its claims and expirySQL Formatter — Break a One-Line Query into Readable ClausesIndent, wrap and case a query, or squash it back to one lineCSS Minifier and Beautifier — Strip a Stylesheet Down or Open It Back UpMinify or re-indent CSS, with the before and after byte countHTTP Status Codes — Full List With What Each One Actually MeansEvery status code, and which side has to fix itASCII Table — Decimal, Hex, Octal and Binary With Control Character NamesAll 128 codes in four bases, plus character lookupMIME Type Lookup — File Extension to Content-Type and BackExtension to Content-Type, with a header you can pasteUnicode Inspector — Code Points, UTF-8 Bytes and Invisible CharactersBreak a string into code points, bytes and clustersJavaScript Keycode Tester — event.key, event.code and keyCode ValuesLive key, code, keyCode and modifier valuesWhat My Browser Reports — User Agent, Screen, Timezone and LocaleWhat every site can read about your browserMeta Tag Generator — Title, Description, Open Graph and Twitter Card TagsA head block with length checks and two previewsrobots.txt Generator — Crawl Rules, Sitemap Lines and AI Bot BlockingA robots.txt with the common mistakes flaggedSitemap Generator — Turn a List of URLs into a Valid sitemap.xmlA URL list becomes valid sitemap XMLSVG Minifier — Strip Editor Metadata, Comments and Excess DecimalsStrips editor cruft, shows before and afterHTML Table Generator — Spreadsheet Paste to table Markup and MarkdownPaste from a spreadsheet, get table markupData Size Converter — KB, MB, GB, TB and KiB, MiB, GiB with Transfer TimeDecimal and binary sizes side by sideBase64 Encoder and Decoder — UTF-8 Safe, With the URL-Safe AlphabetEncode and decode Base64 without mangling UTF-8URL Encoder and Decoder — Percent Encoding for Query Values and Whole URLsPercent-encode a single value or a whole URLURL Parser — Split an Address Into Its Parts and Edit the QueryBreak a URL into parts and rebuild itQuery String Builder and Parser — Take Parameters Apart or Put Them TogetherParse a query string to a table, or build one from a listUTM Builder — Campaign Tracking Links That Do Not Split Your ReportsAdd utm_source, medium and campaign to a linkHTML Escape and Unescape — Entities, and JavaScript String EscapingConvert to and from HTML entities, or escape for a JS stringChmod Calculator — Octal 755, Symbolic rwxr-xr-x and the Special BitsOctal and symbolic permissions, converted both waysRead ls -l Output — Decode rwx Strings, Octal Modes and Risky PermissionsPaste ls -l output, get it read back in plain termsCron Expression Parser — Plain English Reading and the Next Five RunsRead a crontab line and see when it actually firesIPv4 Subnet Calculator — CIDR, Mask, Broadcast and Usable Host RangeCIDR to network, broadcast, host range and maskNumber Base Converter — Binary, Octal, Decimal, Hex and Two’s ComplementAny base 2-36, with two’s complement bit patternsUnix Timestamp Converter — Epoch Seconds and Milliseconds to Local Time and UTCEpoch seconds or milliseconds to a readable date, both waysRegex Tester — Match, Capture Groups and Replace Preview (JavaScript Engine)Test a pattern, see every match, group and replacementLuhn Checksum Validator — Card Number Format Check for Test DataLuhn check digit and issuer-range check for test numbersISBN Validator and Converter — ISBN-10 to ISBN-13 Check Digit CheckCheck an ISBN check digit and convert between 10 and 13 digitsEmail Format Checker — Syntax Validation and Domain Typo DetectionCheck address syntax and catch common domain typosURL Validator and Inspector — Parse a Link and Spot Phishing PatternsBreak a URL into its parts and flag suspicious shapesPassword Strength Estimator — Entropy, Patterns and Crack TimeEntropy estimate, pattern penalties and crack-time figures
Image Tools
8Image to Base64 — Data URL, img Tag and CSS Snippet, Nothing UploadedTurn a file into a data: URL with the HTML and CSS to paste itBase64 to Image — Decode a Data URL, Preview It and Save the FilePaste the string, see the picture, download it with the right extensionCrop Image to Ratio — 1:1, 4:5, 16:9, 9:16 and Custom, in the BrowserCut to a fixed aspect ratio, choosing which edge is keptRotate and Flip an Image — 90, 180, 270 Degrees and Mirroring, No UploadQuarter turns and mirroring, baked into the pixelsImage Info and EXIF Viewer — Dimensions, Format and Whether GPS Is AttachedReal format, pixel size, colour depth and what the metadata revealsFavicon Generator — PNG Set, Link Tags and Web Manifest from One ImageSix PNG sizes plus the head tags and manifest, built in the browserImage Resizer — Change Pixel Dimensions in the Browser, Nothing UploadedSet width or height, keep the proportions, download the resultImage Compressor — Shrink JPEG and WebP Files Without Uploading ThemRe-encode at a chosen quality, cap the long edge, see the saving
Text
24Multi Find and Replace — Apply Many Search-and-Replace Rules in One PassRun a list of find/replace rules over text in orderCharacter Frequency Counter — Letter Counts, Percentages and a Ranked ChartCount how often each character appears, ranked with percentagesBatch Line Cleaner — Trim, Dedupe, Sort, Number and Join a List in One PassRun trim, dedupe, sort, prefix, numbering and join in a fixed orderList Compare — Find What Two Lists Share and What Only One of Them HasCompare two lists: in both, only in A, only in B, combinedTable to Markdown — Convert a Spreadsheet Paste or CSV into Markdown, HTML and JSONTurn a pasted spreadsheet range or CSV into a Markdown, HTML or JSON tableMarkdown Preview — Render Basic Markdown and Copy the HTMLRender core Markdown and get the HTML sourceCSV Table Cleaner — Find Ragged Rows, Drop Blanks and Duplicates, Profile Every ColumnInspect a pasted CSV for ragged rows, blanks and duplicates before you load itText Anonymizer — Redact Emails, Phone Numbers, SSNs, Cards, IPs and AddressesPattern-match a block of text and mask the contact details and ID numbers in itText Template Filler — Merge a Table Into One Message Per RowFill {placeholders} from a pasted table and get one message per rowNumber Format Cleaner — Strip Currency Symbols, Commas and Accounting ParenthesesTurn a column of formatted amounts into numbers a spreadsheet will actually add upBullet Outline Maker — Number an Indented List and Budget the Word CountTurn an indented scratch list into a numbered outline with a word budgetCitation Formatter — Build APA, MLA, Chicago and IEEE Reference EntriesTurn a list of sources into a formatted reference list with in-text examplesCase Converter — camelCase, snake_case, kebab-case, Title Case and BackRe-case text between camel, snake, kebab, constant and prose formsLine Tools — Remove Duplicate Lines, Sort, Trim and Number a ListDedupe, sort, trim and number a list of linesSlug Generator — Turn a Title into a Clean URL SlugTitles to hyphenated, URL-safe slugsText Statistics — Word Count, Sentence Length and Readability ScoresCounts, sentence lengths and readability in one passText Diff — Compare Two Versions Line by LineLine-by-line comparison of two versionsWord Frequency Counter — Which Words You Actually RepeatRanked word counts with a tab-separated exportReading Time Estimator — Word Count to Minutes, With an Editable Reading SpeedHow long a piece takes to read silently or aloudSpeech Time Estimator — Script Word Count to Talk Length, With a Pause AllowanceHow long a script runs when spoken, including pausesKeyword Density Checker — Term Counts, Placement and Distribution in a DraftHow often terms appear in a draft and where they clusterSocial Preview Trimmer — Character Limits and Where Each Platform TruncatesCharacter count against platform limits, with the cut point markedHashtag Generator — Pull Tags From Post Text and Check Them Against Platform LimitsExtract tags from your own text and format them for postingText Similarity Checker — Jaccard, Cosine and Levenshtein Ratio Between Two TextsThree overlap measures between two pieces of text
Random & Generators
6Random Number Generator — Numbers in a Range, Dice Rolls and Coin FlipsNumbers in a range, plus dice and coin modesRandom Picker — Draw Names or Items From a List, With Optional WeightsDraw one or several items from a list, weights supportedDecision Wheel — Spin a Wheel to Pick One Option From a ListA spinning wheel that picks one of your optionsTeam Divider — Split a Name List Into Random Groups of Even SizeSplit a list of names into random, evenly sized teamsSequence Generator — Number, Date, Letter and Zero-Padded List BuilderBuild number, date, letter or padded lists with a prefix and suffixCountdown Maker — Live Days, Hours, Minutes and Seconds to a DateA live countdown to any date and time, or a count-up since one
Shop Math
6Weighted Decision Matrix — Score Options Against Weighted Criteria and See Which Criterion Is Driving the ResultWeight your criteria, score each option, see what flips the rankingPros and Cons Scorer — Weight Each Point 1-5 Instead of Counting the ListsRate each pro and con 1-5 and compare the weighted totals, not the line countsTask Priority Matrix — Sort a Task List Into Four Quadrants and Fill Today From the TopSort tasks by importance and urgency, then fill the hours you actually haveBusiness Day Calculator — Working Days Between Two Dates, or the Date N Business Days OutCount working days, or find the date N business days from a start dateSplit a Bill by Item — Per-Person Totals With Tax, Tip and Shared DishesCharge everyone for what they ordered, share what was shared, spread tax and tip fairlyCooking Measurement Converter — US Cups, Spoons and Ounces Against Metric and ImperialConvert cups, spoons, fluid ounces, pints and gallons across US, metric and imperial
Design & CSS
8CSS Unit Converter — px to rem, em, pt, Percent, vw and vhOne length in every CSS unit, against your own base sizesColor Contrast Checker — WCAG AA and AAA Ratio for Text and UIWCAG contrast ratio, pass and fail by criterion, nearest passing colorCSS Gradient Generator — linear, radial and conic With Live PreviewTwo or three stops to a pasteable linear, radial or conic gradientCSS box-shadow Generator — Offset, Blur, Spread and Layered ShadowsBuild a one or two layer box-shadow and copy the CSSCSS border-radius Generator — Per Corner, Percent and EllipticalPer-corner radii, shorthand and longhand, elliptical slash syntaxCSS Grid Generator — grid-template Columns, Rows and Named AreasColumn and row tracks, named areas, HTML skeleton and a mobile breakpointAspect Ratio Calculator — Reduce Pixel Dimensions and Resize Without DistortionLowest-terms ratio, the missing dimension, and crop mathsPPI Calculator — Pixel Density, Dot Pitch and Retina Viewing DistanceResolution plus diagonal inches gives density, pitch and viewing distance
Color
2Color Converter — HEX to RGB to HSL, with White or Black Text ContrastHEX ↔ RGB ↔ HSL plus the WCAG contrast for text on itColor Palette Generator — Complementary, Analogous and Tint Scales from One Base ColorSix harmony rules plus a 9-step scale, with contrast on every swatch
Converters
6Morse Code Translator — Text to Morse and Back, With Audio at Your WPMText to morse and back, with playback at a chosen WPMBraille Converter — English Grade 1 Uncontracted Braille With Dot NumbersText to uncontracted braille cells and dot numbersText to Binary Converter — Binary, Octal and Hex From UTF-8 BytesText to binary, octal or hex bytes, and back againRoman Numeral Converter — Numbers to Roman Numerals and Back, With ValidationNumbers to roman numerals and back, with a validity checkNumber to Words Converter — Write Any Amount Out in English, Including ChequesNumbers written out in words, cheque format and ordinalsReverse Text Tool — Flip Characters, Words or Lines, and Clean Up SpacingReverse characters, words or lines, and tidy spacing