Free Online Developer Tools

Regex tester, JWT decoder, SQL formatter, cURL to code and 21 free developer tools.

21 free developer tools — no sign-up needed
21 tools in
this category

JWT Decoder

Read the header and payload of a JSON Web Token, including expiry times.

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Regex Tester

Test a regular expression against sample text and inspect every match and group.

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Cron Expression Parser

List the next run times for a five-field cron schedule, in UTC.

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HTTP Status Code Lookup

Look up what an HTTP status code means, or search the full list.

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Code Beautifier

Auto-format messy JavaScript, HTML or CSS with consistent indentation.

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Syntax Highlighter

Turn a code snippet into highlighted HTML you can paste into a blog post or page.

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Regex Cheat Sheet

A searchable quick reference for common regular expression syntax.

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SQL Formatter

Break a SQL query onto multiple lines at major keywords for easier reading.

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JSON to TypeScript Interface Generator

Infer a TypeScript interface from a sample JSON object.

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cURL Command Builder

Build a cURL command from a method, URL, headers and body.

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JWT Encoder

Build and sign a JSON Web Token from a header, payload and secret.

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cURL to Code Converter

Paste a curl command and get the same request as JavaScript, Python or Node.js code.

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.gitignore Generator

Pick the languages and tools you use and get a merged .gitignore file.

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.env / JSON Converter

Convert environment variables between .env file format and a JSON object.

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SemVer Parser and Comparator

Break a semantic version into its parts, and compare two versions.

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Git Command Cheat Sheet

A searchable quick reference for the git commands you use most.

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HTTP Headers Formatter

Parse a raw block of HTTP headers into a table or JSON, or build one from a table.

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Mock JSON Data Generator

Define a simple schema and generate fake JSON records to test against.

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Code Minifier

Minify JavaScript, CSS or HTML using the same real minifiers bundlers use — Terser, csso and html-minifier-terser.

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URL Shortener

Turn a long link into a short one that redirects visitors to the original address.

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Cron Expression Generator

Build a five-field cron expression from simple fields or presets, and see its next run times.

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Explore other categories

Text Tools

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Generators

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Image Tools

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Designer Tools

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SEO Tools

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About

About Developer Tools

Toolapt's 21 free online developer tools take care of the small, fiddly jobs in everyday development. Test regular expressions against sample text with the Regex Tester and keep the Regex Cheat Sheet open for syntax; decode a JSON Web Token's header and payload or sign a new one; beautify, minify or syntax-highlight JavaScript, CSS and HTML; and format SQL queries so they're easy to read. Build cURL commands or convert them into JavaScript, Python or Node.js code, look up HTTP status codes, build cron expressions and see when a schedule runs next, and generate a TypeScript interface from sample JSON. There are also tools to generate a .gitignore, convert .env files to JSON, parse semantic versions, format HTTP headers, create mock JSON data and shorten URLs, plus a searchable git cheat sheet. No account, no install and no limit.

A few to try

FAQ

Frequently asked questions

Quick answers to the questions people ask most.

How do I test a regular expression?

Paste your pattern and some sample text into the Regex Tester. It highlights every match and shows each capture group, and the Regex Cheat Sheet is there if you need a syntax reminder.

How do I decode a JWT?

Paste the token into the JWT Decoder to read its header and payload, including when it expires. To create and sign a new token, use the JWT Encoder.

How do I format a SQL query?

Paste the query into the SQL Formatter. It breaks it onto separate lines at major keywords such as SELECT, FROM, WHERE and JOIN so it's easy to read.

How do I convert a cURL command to code?

Paste the curl command into cURL to Code Converter and get the same request as JavaScript, Python or Node.js code. To write a curl command from scratch, use the cURL Command Builder.

How do I beautify or minify JavaScript, CSS or HTML?

Use the Code Beautifier to indent messy code cleanly, and the Code Minifier to shrink it — it uses the same real minifiers build tools use: Terser for JavaScript, csso for CSS and html-minifier-terser for HTML.

How do I build or check a cron expression?

Use the Cron Expression Generator to build a schedule from simple fields or presets, and the Cron Expression Parser to list the next run times of an expression you already have.

How do I create a .gitignore file?

Open the .gitignore Generator, pick the languages, frameworks and tools you use, and it merges the right ignore rules into one .gitignore file you can copy or download.

Where are the robots.txt, meta tag and sitemap generators?

They're in the SEO Tools category, together with the .htaccess Generator, keyword density checker and other tools for search engine optimization.

Are these developer tools free? Do I need to sign up?

All 21 developer tools are completely free, with no account and no limit on how often you use them. They work in any modern browser on phone, tablet and desktop.

Is my code or data sent to a server?

No — every developer tool works in your own browser, so code, tokens and secrets you paste stay on your device. The one exception is the URL Shortener: it has to store your long link so the short link can redirect to it.

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