Developer Tools

001 popular

JSON Formatter

Formats, indents and validates JSON with precise error positions, key sorting and a…

002 popular

JSON Validator

Checks whether JSON is valid and reports the exact line, column and reason for the first error…

003

JSON Minifier

Strips all whitespace from JSON to produce the smallest valid output, showing the bytes saved.

004 popular

JSON to CSV Converter

Converts a JSON array of objects into CSV, flattening nested keys and handling missing fields…

005 popular

CSV to JSON Converter

Turns CSV or TSV into a JSON array of objects, with type detection for numbers and booleans.

006

JSON to XML Converter

Converts JSON into well-formed XML with a configurable root element and array item naming.

007

XML to JSON Converter

Parses XML and converts it to JSON, preserving attributes and handling repeated elements as…

008

JSON to YAML Converter

Converts JSON to clean YAML with correct indentation, quoting and multi-line string handling.

009

YAML to JSON Converter

Parses YAML and outputs equivalent JSON, with support for anchors, lists and nested maps.

010

JSON Escape and Unescape

Escapes a string for safe embedding inside JSON, and unescapes a JSON string back to plain text.

011

JSONPath Tester

Runs a JSONPath expression against your JSON and shows the matched values live.

012

JSON Schema Generator

Infers a JSON Schema (draft 2020-12) from a sample JSON document, with required fields and…

013

JSON Diff Checker

Compares two JSON documents structurally and lists every added, removed and changed key path.

014

XML Formatter

Formats and validates XML with proper indentation, and reports the position of any parse error.

015 popular

HTML Formatter

Indents and tidies HTML, closing implied tags and normalising attribute spacing without…

016

HTML Minifier

Removes comments, redundant whitespace and optional quotes from HTML, showing the size saved.

017

CSS Formatter

Formats CSS with consistent indentation, one declaration per line and sorted properties if you…

018 popular

CSS Minifier

Minifies CSS by removing comments, whitespace and redundant syntax, reporting the exact bytes…

019

JavaScript Formatter

Formats and indents JavaScript so minified or badly formatted code becomes readable again.

020

JavaScript Minifier

Strips comments and unnecessary whitespace from JavaScript to reduce file size safely.

021 popular

SQL Formatter

Formats SQL queries with proper keyword casing, indentation and line breaks for MySQL…

022

SQL Minifier

Collapses a formatted SQL query into a single line, stripping comments and extra whitespace.

023 popular

Markdown to HTML Converter

Converts Markdown to clean HTML with tables, code blocks, task lists and a live preview.

024

HTML to Markdown Converter

Converts HTML back into readable Markdown, keeping links, lists, tables, headings and code…

025

Markdown Table Generator

Builds properly aligned Markdown tables from CSV, TSV or pasted spreadsheet data.

026 popular

Base64 Encoder and Decoder

Encodes text to Base64 and decodes Base64 back to text, with URL-safe mode and full UTF-8…

027 popular

URL Encoder and Decoder

Percent-encodes and decodes URLs and query strings, with separate component and full-URI modes.

028

HTML Encoder and Decoder

Converts characters to HTML entities and back, protecting text from being interpreted as markup.

029 popular

JWT Decoder

Decodes a JSON Web Token and shows the header, payload and claims in readable form, with…

030

URL Parser

Breaks any URL into protocol, host, port, path, query parameters and fragment, with each…

031

Query String Parser

Converts a query string into a readable table of keys and values, and rebuilds a query string…

032 popular

Unix Timestamp Converter

Converts Unix epoch timestamps to human-readable dates in any time zone, and dates back to…

033 popular

Cron Expression Parser

Explains any cron expression in plain English and lists the next ten times it will run.

034

Cron Expression Generator

Builds a cron expression from plain choices — every N minutes, weekdays only, a specific time…

035 popular

Regex Tester

Tests regular expressions live against sample text, highlighting every match and capture group…

036

Code Diff Checker

Compares two code files line by line with syntax-aware whitespace handling and a unified diff…

037

String Escape and Unescape

Escapes strings for JavaScript, Java, C, Python, SQL, CSV and shell, and reverses each escaping.

038

Hex to ASCII Converter

Converts hexadecimal to readable text and text to hex, with optional spacing and 0x prefixes.

039

ASCII Table

A searchable ASCII and extended ASCII reference with decimal, hex, octal, binary and HTML…

040

Unicode Character Lookup

Inspects any character and shows its code point, name, UTF-8 bytes, HTML entity and escape…

041

Line Ending Converter

Converts between Windows CRLF, Unix LF and classic Mac CR line endings and reports what the…

042

Tabs to Spaces Converter

Converts tab indentation to spaces or spaces back to tabs, at any tab width.

043 popular

UUID Generator

Generates cryptographically random UUIDs in versions 4 and 7, plus nil and max UUIDs, in bulk.

044

HTTP Status Code Reference

A searchable list of every HTTP status code with its meaning, when to use it and common causes.

045

MIME Type Lookup

Finds the MIME type for any file extension and the extensions matching any MIME type.

046

User Agent Parser

Breaks a user agent string into browser, engine, operating system and device, and shows your…

047

Subnet Calculator

Calculates network address, broadcast, usable host range, wildcard mask and host count from an…

048

IP Address Converter

Converts IPv4 addresses between dotted decimal, integer, binary and hexadecimal notation.

049

MAC Address Generator

Generates random MAC addresses in any format, with optional vendor prefix and locally…

050

Port Number Lookup

Searchable reference of well-known and registered TCP and UDP ports and the services that use…

051 popular

htaccess Redirect Generator

Generates correct .htaccess rules for 301 redirects, HTTPS forcing, www handling and trailing…

052

cURL to Code Converter

Converts a cURL command into equivalent JavaScript fetch, Python requests, PHP cURL or Node…

053

PHP Serialize and Unserialize

Converts PHP serialized strings to readable JSON and back, useful for debugging WordPress and…

054

.env to JSON Converter

Converts a .env file into JSON or YAML, handling quotes, comments and multi-line values.

055

Text to JSON Array Converter

Converts a list of lines into a JSON array of strings, numbers or objects with a key you choose.

056

CSV to SQL Converter

Generates INSERT statements or a CREATE TABLE definition from CSV data, with type inference…

057

SQL IN Clause Builder

Turns a pasted list into a properly quoted SQL IN clause, splitting into batches when the list…

058 popular

Random JSON Data Generator

Generates realistic mock JSON data — names, emails, addresses, dates, prices — from a schema…

059

ASCII Art Text Generator

Turns short text into large ASCII art banners in several block-letter styles.

060

HTML Entity Lookup

Searchable table of HTML entities with their named, decimal and hexadecimal forms and a live…

061

Meta Viewport Generator

Builds the correct viewport meta tag for responsive pages and explains what each property does.

062

UUID Validator

Checks whether a UUID is valid and reports its version and variant, decoding the timestamp…

063

Semantic Version Comparator

Compares two semantic versions and says which is newer, what level of change it is, and…

064 popular

SRT to VTT Converter

Converts subtitles between SubRip and WebVTT, fixing the timestamp separator and header, and…

065

Subtitle Timing Shifter

Shifts every subtitle cue forward or back by a set number of seconds, and can rescale the…

066

HTTP Header Analyzer

Reads pasted HTTP response headers and reports which security and caching headers are missing…

067 popular

ZIP File Creator

Packs any set of files into a single .zip archive inside your browser, with a choice of…

068 popular

ZIP Extractor

Opens a .zip archive in your browser and lets you download the files inside individually…

069

ZIP Contents Viewer

Lists every file inside a .zip with its size, compressed size, saving and date, without…

070

ZIP Compression Comparer

Zips the same files at every compression level and shows the real size and time for each, so…

071

Folder to ZIP

Packs an entire folder into one .zip in your browser, keeping the subfolder structure, with an…

072

Gzip Compressor

Compresses text or a file to gzip, deflate or raw deflate using the browser's built-in…

073

Gzip Decompressor

Decompresses a .gz, zlib or raw deflate file in your browser and shows the text or hands back…

074

Gzip Size Estimator

Measures the real gzipped size of CSS, JS, HTML or JSON and shows the transfer time saved…

075

Deflate and Base64 Tool

Compresses text to gzip, zlib or raw deflate and returns base64, or expands a pasted base64…

076

Compression Ratio Calculator

Converts between compression ratio, percentage saved and bits per byte, and works out the…

077

Discord Timestamp Generator

Turns a date and time into a Discord timestamp tag in all seven styles, each shown as it will…

078 popular

SPF Record Checker

Checks an SPF record for the ten-lookup limit, a deprecated ptr, a missing all and other…

079

SPF Record Generator

Builds an SPF record from your mail sources and counts the DNS lookups as you go, so you see…

080 popular

DMARC Record Generator

Builds a DMARC record with policy, reporting addresses and alignment, and warns when reports…

081

DMARC Record Checker

Validates a DMARC record tag by tag, explaining what each one does and flagging the mistakes…

082

DKIM Record Formatter

Turns a DKIM public key into a DNS TXT value and splits it into the 255-character strings a…

083 popular

Email Header Analyzer

Reads raw email headers and shows the delivery path with per-hop delays, the SPF, DKIM and…

084

DNS Propagation Time Calculator

Works out how long a DNS change takes to be seen everywhere, from the TTL that was published…

085

Email Bounce and Blocklist Explainer

Reads an SMTP bounce and identifies the blocklist that rejected the message, what it means and…

086 popular

LLM Token Counter

Estimates how many tokens a piece of text costs, broken down by script, and shows what…

087 popular

LLM API Cost Calculator

Works out what an LLM feature costs per call, month and year, including what prompt caching…

088

Context Window Planner

Works out how many conversation turns fit in a context window once the system prompt, tools…

089

System Prompt Linter

Checks a system prompt for the patterns that reliably cause trouble, and shows what it costs…

090

JSON Schema to Tool Definition

Wraps a JSON Schema into a tool definition for OpenAI, Anthropic or Gemini, and flags…

091

Chat Transcript Splitter

Splits a long transcript into chunks under a token budget, breaking on speaker turns rather…

092

Embedding Cost Estimator

Estimates what embedding a corpus costs, how many chunks it produces, and how much vector…