A workbench of developer tools that never leave your browser.
Free developer tools that run entirely in your browser: format JSON, generate UUIDs, count words and more. No upload, no sign-up, nothing sent to a server.
JSON & data formats
CSV to JSON ConverterCSV into JSON with a parser that survives quotes and line breaks.JSON DiffCompare two JSON documents by value, with a JSON Patch out.JSON Escape and UnescapeTurn text into a JSON string value, and back.JSON FormatterBeautify, minify and validate JSON instantly.JSON to CSV ConverterJSON arrays into CSV that Excel opens without mangling a column.JSON to TOML ConverterJSON into TOML 1.0 tables, with the path of every null.JSON to TypeScript ConverterJSON in, TypeScript interfaces out — unknown, never any.JSON to YAML ConverterJSON into YAML, quoted where YAML would misread it.XML FormatterIndent or minify XML, with the broken tag named.YAML to JSON ConverterYAML into JSON, anchors resolved, errors with line numbers.
Code & SQL formatters
CSS BeautifierUnminify and indent CSS, one declaration per line.CSS MinifierStrip comments and whitespace from CSS, safely.HTML FormatterIndent or minify HTML without changing how it renders.Markdown Table GeneratorGrid or pasted CSV into an aligned GFM table.Markdown to HTML ConverterRender a declared CommonMark subset to HTML.MySQL FormatterBeautify MySQL, backticks and # comments included.PostgreSQL FormatterBeautify Postgres SQL, dollar quoting and casts included.SQL FormatterBeautify or minify SQL, with strings and comments intact.
Cron schedules
Cron Every 15 MinutesA quarter-hour schedule, with the offsets.Cron Every 30 MinutesHalf-hourly schedules, and the trap next door.Cron Every 5 MinutesA five-minute schedule, and how to offset it.Cron Every Day at MidnightA daily midnight job that survives the clocks.Cron Every HourHourly, two-hourly and six-hourly schedules.Cron Every MinuteRun a job every minute, without stacking runs.Cron Every MondayWeekly Monday jobs, without the off-by-one.Cron Every MonthMonthly and quarterly jobs, last day included.Cron Expression GeneratorExplain a cron schedule and preview its next runs.
Encoding & hashing
Base64 Encoder and DecoderEncode and decode Base64 with correct UTF-8.Hash GeneratorSHA-1, SHA-256, SHA-384 and SHA-512 digests of any text.HTML Entity Encoder and DecoderEscape and unescape HTML entities safely.Image to Base64 ConverterImage to data URI and back, without uploading the file.JWT DecoderRead a JWT header, payload and expiry safely.MD5 GeneratorMD5 of text or a file, with a checksum comparison.Morse Code TranslatorText to Morse and back, with the whole ITU table on the page.Number Base ConverterAny base from 2 to 36, with BigInt precision.Text to Binary ConverterTurn text into UTF-8 bits, and bits back into text.URL Encoder and DecoderPercent-encode and decode URLs and query values.
Network & web
Chmod CalculatorTurn file permissions into octal, symbolic form and a command.CIDR CalculatorIPv4 prefixes, host ranges and usable counts.HTTP Status CodesAll 63 registered codes, searchable, plus the ones servers invented.IP Address ConverterEvery way to write one IPv4 or IPv6 address, side by side.MIME Type LookupExtension to media type and back, with the header to send.URL ParserEvery part of a URL, named and explained.
Generators
Code 128 Barcode GeneratorShortest Code 128 barcode for any ASCII text, as SVG or PNG.EAN-13 Barcode GeneratorEAN-13 barcodes as SVG or PNG, with the check digit.Fake Data GeneratorMock rows as JSON, CSV or SQL, reproducible by seed.Password GeneratorRandom passwords and passphrases, with honest entropy.QR Code GeneratorQR codes for links, text and Wi-Fi, as SVG or PNG.Random Number GeneratorPick numbers in a range, drawn without modulo bias.ULID GeneratorGenerate sortable ULIDs and decode their timestamp.UUID GeneratorGenerate UUID v4 and v7 identifiers in bulk.
Text & regex
Case ConverterNine naming conventions from any input, acronyms included.Lorem Ipsum GeneratorPlaceholder paragraphs, sentences or words, as text or HTML.Regex TesterMatch, replace and read a regular expression.Remove Duplicate LinesStrip repeated lines from a list and count what went.Slug GeneratorTitles into clean URL slugs, accents folded.Sort LinesSort lines alphabetically, naturally, numerically or by length.Text Diff CheckerLine-by-line comparison with word-level highlighting.Word CounterCount words, characters and reading time as you type.Word Frequency CounterRank words and phrases by how often they occur, then export.
Units, time & colour
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