DEVELOPER TOOLS
Format, encode, hash, and inspect data. Pick one below — every one of them runs right in your browser, nothing is uploaded.
JWT Decoder
Paste a JWT, see the header, payload, and claims — and verify the signature.
Base64 Encoder
Encode text to Base64 or decode it back, with correct UTF-8 handling.
URL Encoder / Decoder
Percent-encode or decode text and URLs, component or full-URL scope.
HTTP Status Code Lookup
Search HTTP status codes by number or name to see their meaning.
HMAC Generator
Compute an HMAC-SHA1/256/384/512 of a message with a secret key, right in your browser.
Query String Parser & Builder
Parse a URL's query string into key/value rows, or build a query string from scratch.
JWT Generator
Build and sign a JSON Web Token (HS256/384/512) from a header, payload, and secret.
Password Strength Checker
Estimate a password's entropy and crack time, with specific tips to make it stronger.
PIN Generator
Generate random numeric PINs of any length, with an option to avoid adjacent repeats.
Data URI Generator
Turn a file into a data: URI you can paste straight into CSS or HTML, with a live preview.
Unix Timestamp Converter
Convert Unix/epoch timestamps to human-readable dates in UTC and your local timezone, or a date back to a timestamp — client-side, no upload.
HTML/CSS/JS Beautifier & Minifier
Beautify or minify HTML, CSS, and JavaScript instantly in your browser — no upload, no account.
CSV ⇄ JSON Converter
Convert CSV to JSON or JSON back to CSV, with correct quoted-field and comma handling — entirely in your browser.
YAML ⇄ JSON Converter
Convert YAML to JSON or JSON to YAML instantly in your browser, with clear error messages when parsing fails.
IP Subnet / CIDR Calculator
Calculate network address, broadcast address, subnet mask, wildcard mask, and usable host range from CIDR notation or a dotted subnet mask — entirely in your browser.
XML Formatter & Minifier
Pretty-print XML with correct indentation or strip whitespace to minify it. Catches syntax errors inline — nothing uploaded.
XML to JSON Converter
Convert XML to JSON or JSON back to XML instantly. Attributes become @-prefixed keys, arrays are handled automatically — nothing uploaded.
YAML Validator
Validate YAML syntax instantly and preview the parsed structure as formatted JSON. Clear error messages on failure — nothing uploaded.
HTML Encoder / Decoder
Encode special characters to HTML entities (&, <, >, ") or decode them back to plain text. Updates as you type — nothing uploaded.
UUID Validator
Validate one or many UUIDs at once. Detects version (v1–v8) and variant, normalizes compact or braced formats — nothing uploaded.
Cron Expression Generator
Build cron schedules visually or from presets, copy the expression, and preview the next 5 run times in your local timezone.
CSS Escape Generator
Escape text for a safe CSS class/ID selector or string literal, using the browser's native CSS.escape().
Curl Command Explainer
Paste a curl command and see every flag explained in plain English, with the derived method, URL, and header count.
Curl Command Generator
Build a curl command from a method, URL, headers, auth, and body — pick the options you need and copy the result.
JSON to TypeScript Converter
Paste JSON and get matching TypeScript interfaces, with nested objects turned into their own named interfaces.
Regex Explainer
Paste a regular expression and get a plain-English breakdown of every token, group, and quantifier.
User-Agent Parser
Decode a User-Agent string into browser, version, operating system, device type, and rendering engine.
Email Validator
Check an email address's format, see its local part and domain, and catch common typo domains like gmial.com.
Phone Number Validator
Validate a phone number for any country and see its national, international, and E.164 formats.
Credit Card Number Validator
Check a card number's Luhn checksum and detect its network — nothing is ever transmitted or stored.
IBAN Validator
Validate an IBAN's MOD-97 checksum and check its length against the issuing country's rules.
VIN Decoder & Checksum Validator
Validate a VIN's check digit and decode its manufacturing region and possible model year.
ASCII Table
A searchable reference of all 128 ASCII characters with decimal, hex, octal, and binary codes, plus a live lookup.
Base Converter
Convert numbers between binary, octal, decimal, hexadecimal, and any custom base from 2 to 36.
JSON Schema Validator
Validate JSON data against a JSON Schema and see every failing property with its exact path and reason.
SQL Validator
Catch unbalanced parentheses/quotes, out-of-order clauses, trailing commas, and missing JOIN conditions before you run a query.
SQL Minifier
Strip comments and collapse whitespace from SQL queries while keeping strings and quoted identifiers intact.
ISO 8601 Date Converter
Build or parse an ISO 8601 date/time, with week date, ordinal date, and Unix timestamp forms included.
Questions
- Are these developer tools actually free?
- Yes, all of them. No account, no API key, no rate limit — format, encode, hash, or decode as much as you need.
- Is my data sent to a server?
- No. Every tool here runs client-side in your browser with JavaScript (and the Web Crypto API for hashing/signing) — nothing you paste or upload is ever sent anywhere.
- Which tool do I use to hash or sign something?
- Hash Generator for plain SHA-1/256/384/512 digests, HMAC Generator for a keyed hash, and JWT Generator/JWT Decoder for building or reading a JSON Web Token.
- Can I convert between encodings here?
- Yes — Base64, Hex, Binary, Base32, and Base58 converters each go both directions (text to encoded, and back), so you don't need separate encode/decode tools.