All tools

30 developer tools, grouped by category. Every client tool runs entirely in your browser.

Formatters & Validators

JSON Formatter & ValidatorFormat, validate and minify JSON in your browser. Pretty-print with 2/4-space or tab indent, sort keys, and get parse errors with the exact line and column.SQL FormatterFormat and beautify SQL queries online with dialect-aware indentation for PostgreSQL, MySQL, SQL Server, BigQuery and more. Runs in your browser.HTML FormatterBeautify or minify HTML in your browser. Re-indent messy markup or strip comments and whitespace to shrink payloads. Private, offline, and instant.CSS Beautifier & MinifierMinify CSS online to shrink file size, or beautify messy stylesheets into readable, indented rules. Runs entirely in your browser — nothing is uploaded.JavaScript Beautifier & MinifierBeautify or minify JavaScript in your browser. Re-indent messy code or strip comments and whitespace, with a scanner that understands strings and regex.

Encoders & Decoders

Base64 Encode / DecodeEncode and decode Base64 in your browser with full UTF-8 support and the URL-safe alphabet. Text is converted entirely on your device — nothing is uploaded.JWT DecoderDecode a JWT to read its header and payload without sending it anywhere. See the algorithm, expiry and issued-at times — and why decoding is not verifying.URL Encode / DecodeFree, private URL encoder and decoder that runs entirely in your browser. Percent-encode query values or whole URLs and decode %-escapes instantly.HTML Entity Encode / DecodeEncode and decode HTML entities in your browser — escape <, >, & and quotes, or turn named and numeric references back into text. Private, free, no upload.

Converters

CSV to JSON ConverterConvert CSV to JSON in your browser: RFC 4180 quoting, custom delimiters, and header-to-object mapping. Private and offline — your data never leaves the page.YAML ⇄ JSON ConverterConvert YAML to JSON and JSON to YAML instantly in your browser. Free, private, and offline-capable, with clear parse-error reporting and no uploads.

Generators

UUID Generator (v4 / v7)Generate random v4 and time-ordered v7 UUIDs online, free and private. IDs are created in your browser with a CSPRNG and never sent anywhere.Password GeneratorGenerate strong, random passwords in your browser with adjustable length, character sets, and a live entropy readout. Private and offline, nothing is sent.Lorem Ipsum GeneratorGenerate lorem ipsum placeholder text by paragraphs, sentences, or words. Free, private, and fully in-browser — copy classic filler for mockups instantly.Hash Generator (MD5/SHA-1/256/512)Generate MD5, SHA-1, SHA-256 and SHA-512 hashes from text in your browser. See all four digests at once, computed locally so nothing is uploaded.QR Code GeneratorGenerate QR codes from any URL or text in your browser, free and private. Tune error correction and download a crisp, scalable SVG — nothing is uploaded.

Text Tools

Case ConverterConvert text between camelCase, snake_case, kebab-case, PascalCase, CONSTANT_CASE and dot.case. Free, private, and runs entirely in your browser.Word & Character CounterCount words, characters, sentences, paragraphs, and reading time instantly. A free, private word & character counter that runs entirely in your browser.Line Sorter & DeduplicatorSort lines alphabetically or numerically and remove duplicate or blank lines, right in your browser. Case-insensitive, locale-aware, and fully private.Text Diff CheckerCompare two blocks of text or code online and see added, removed, and unchanged lines instantly. A free, private line diff that runs in your browser.Markdown PreviewPreview Markdown online with a live GitHub-flavored renderer. Tables, code blocks, and task lists render instantly and privately in your browser.

Crypto & Security

Regex Tester & DebuggerTest and debug regular expressions online in your browser. See every match, numbered and named capture groups, and flag toggles — private, nothing uploaded.

Date & Time

Unix Timestamp ConverterConvert a Unix epoch timestamp to a human date (and back) with ISO 8601, UTC, and local time. Auto-detects seconds vs milliseconds, fully in-browser.Cron Expression GeneratorBuild a cron expression from presets or your own edits and preview the next five run times in your local timezone. Runs entirely in your browser.

CSS & Design

Color ConverterConvert colors between HEX, RGB and HSL in your browser with a live swatch. Handles alpha, #RGB shorthand and rgb()/hsl() syntax — private and free.

Web & Network

DNS LookupLook up DNS records for any domain — A, AAAA, MX, TXT, NS, CNAME and SOA. Runs on our server so it works even behind a locked-down or private network.SSL Certificate CheckerCheck a site's SSL/TLS certificate from our server: expiry date, days remaining, issuer, subject and the SAN list — even for expired or self-signed certs.HTTP Header CheckerCheck the HTTP response headers of any URL: see the status, cache and cookie rules, plus security headers like HSTS, CSP, and nosniff. Server-side lookup.URL Metadata / OG PreviewPreview the Open Graph card Slack, Discord, and social sites build from a URL. Our server fetches the page and reads its og:title, og:image, and meta tags.What Is My IPSee the public IP address the internet uses to reach you, not your private LAN address, plus your user-agent and any proxy chain. A server-side lookup.