Free Developer Tools

Instant tools for developers and AI agents. No signup. No accounts. No tracking. Just tools that work.

Browser-based — nothing sent to servers
REST API for agents & scripts
Zero signup required
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LLM Token Counter

Count tokens and estimate API costs for Claude, GPT-4o, Gemini, Mistral and more. See which models your text fits in.

AICost calculatorBrowser
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JWT Decoder

Decode and inspect any JWT token instantly. See header, payload, claims, expiry time, and algorithm — no secret needed.

AuthSecurityBrowser
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JSON Formatter

Beautify or minify JSON with syntax highlighting, error detection, and stats. Keyboard shortcut Ctrl+Enter to format.

JSONFormatterValidator
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Base64 Encoder / Decoder

Encode text or files to Base64 and decode Base64 strings. Supports URL-safe mode and file-to-data-URI conversion.

EncodingFilesBrowser
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Regex Tester

Test regular expressions with real-time match highlighting, capture group display, and replace preview. Includes common patterns.

RegexPattern matchingBrowser

Cron Generator

Build cron expressions with a visual interface or parse any existing cron expression. Shows plain-English description and next run times.

SchedulingDevOpsBrowser
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Fake Data Generator

Generate realistic test data: names, emails, addresses, companies, UUIDs, colors and more. JSON output with reproducible seeds.

TestingMock dataREST API
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DNS Lookup

Query A, AAAA, MX, TXT, NS, CNAME, SOA and PTR records for any domain. Instant results via our server-side resolver.

DNSDevOpsREST API
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Hash Generator

Generate MD5, SHA-1, SHA-256, and SHA-512 hashes instantly. All hashing runs client-side via Web Crypto API.

SecurityCryptoBrowser
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URL Encoder / Decoder

Percent-encode URLs and query strings, or decode %XX sequences. Supports encodeURIComponent and encodeURI modes.

URLsWebBrowser
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Password Generator

Generate cryptographically secure random passwords. Choose length, character sets, and generate up to 10 at once.

SecurityRandomBrowser
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Unix Timestamp Converter

Convert Unix timestamps to human-readable dates and back. Live clock, ISO 8601, UTC, local time, and relative display.

TimeDevOpsBrowser
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UUID Generator

Generate UUID v4 identifiers instantly. Bulk generate up to 100. Supports uppercase, no-hyphens, and brace formats.

IDsDatabaseBrowser
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HTTP Status Codes

Complete reference for all HTTP status codes — 1xx to 5xx. Searchable with explanations and "when to use" tips.

HTTPAPIReference
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Git Cheat Sheet

Complete git commands reference with examples — setup, branching, merging, rebasing, stashing, undoing mistakes.

GitVersion ControlReference
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SQL Cheat Sheet

SQL commands with examples — SELECT, JOIN types, GROUP BY, window functions, CTEs, indexes. Works with PostgreSQL, MySQL, SQLite.

SQLDatabaseReference
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Docker Cheat Sheet

Complete Docker commands reference — containers, images, volumes, networks, Docker Compose, Dockerfile, and debugging.

DockerDevOpsReference
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Linux Commands Cheat Sheet

Bash and Linux commands with examples — file operations, permissions, grep, awk, sed, processes, networking, and shell scripting.

LinuxBashReference
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LLM Cost Calculator

Compare API costs for GPT-4o, Claude, Gemini, DeepSeek, and 14+ other LLMs. Enter your token usage and find the cheapest model.

LLMsAIPricing
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MCP Server Directory

Setup guides and configs for 20+ Model Context Protocol servers — filesystem, GitHub, Postgres, Brave Search, and more.

MCPClaudeAgents

Also available as a free REST API

All tools are accessible programmatically — perfect for AI agents, scripts, and CI pipelines. No API key needed.

Hatchloop Pro

Need higher limits?

10,000 API requests/day · Bulk generation up to 500 items · Priority support · No attribution

Upgrade to Pro — $9/mo →
Cancel anytime · Billed monthly via Polar