Code, APIs, debugging
Developer Tools
Fast browser tools for JSON, formatting, encoding, hashing, regex, timestamps, Firebase, Android, and daily developer workflows.
Collection includes
64
free tools, no signup
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Featured Developer Tools
JSON
JSON Viewer
Visualize and explore JSON data in a collapsible tree
Use tool ->JSON
JSON Formatter
Beautify or minify your JSON instantly
Use tool ->Developer
JSON to TypeScript Interface
Generate TypeScript interfaces from JSON objects and arrays with optional root interface name
Use tool ->Developer
JWT Decoder & Inspector
Decode JWT header, payload, expiry, and claims locally in your browser
Use tool ->Converter
Unix Timestamp Converter
Convert Unix timestamps, epoch time, UTC, local dates, and milliseconds instantly
Use tool ->Developer
Regex Tester
Test and debug regular expressions
Use tool ->Browse all
All tools in this collection
JSON
JSON Path Finder
Find and copy dot paths, bracket paths, and values from nested JSON objects and API responses
Use tool ->JSON
JSON Schema Generator
Generate JSON Schema from sample JSON with inferred types, required fields, arrays, and nested objects
Use tool ->Developer
Color Contrast Checker
Check WCAG color contrast ratio for text and background colors with preview and CSS output
Use tool ->Developer
Base64 Encoder/Decoder
Encode and decode Base64 strings
Use tool ->Developer
Image to Base64 Converter
Convert images to Base64 strings or Data URLs locally with preview, copy, and download
Use tool ->Developer
Hash Generator
Generate MD5, SHA, and HMAC hashes from text or files
Use tool ->Formatter
SQL Formatter
Format, beautify, minify, and clean SQL queries online
Use tool ->Formatter
XML Formatter
Format, beautify, minify, and validate XML strings with copyable output
Use tool ->Formatter
HTML Formatter
Format or minify HTML markup for readable templates, snippets, and emails
Use tool ->Formatter
CSS Minifier
Minify CSS by removing comments, whitespace, and unnecessary formatting for smaller stylesheets
Use tool ->Formatter
JavaScript Minifier
Minify JavaScript snippets by removing comments, whitespace, and formatting for quick compact output
Use tool ->Developer
CSS Specificity Calculator
Calculate CSS selector specificity, compare selectors, and find which rule wins
Use tool ->Developer
URL Encoder/Decoder
Encode or decode URL strings
Use tool ->Developer
URL Parser
Parse URLs into protocol, host, path, hash, query parameters, UTM tags, and copyable reports
Use tool ->Developer
Color Converter
Convert between HEX, RGB, and HSL
Use tool ->Developer
Password Strength Checker
Check password strength, entropy, crack-time estimate, and improvement tips locally
Use tool ->Developer
HTTP Status Code Lookup
Look up HTTP status codes, meaning, category, and practical API debugging guidance
Use tool ->Developer
MIME Type Lookup
Find MIME types by file extension or extension by MIME type for web uploads and headers
Use tool ->Developer
HTTP Header Parser
Parse raw HTTP response headers, inspect cache, security, CORS, content type, and copy a readable report
Use tool ->Developer
CSP Generator
Generate Content-Security-Policy headers for scripts, styles, images, fonts, frames, connections, and forms
Use tool ->Developer
Security Headers Generator
Generate starter security headers for HSTS, CSP, frame protection, referrer policy, permissions policy, and MIME sniffing
Use tool ->Developer
Redirect Rule Generator
Generate redirect rules for Vercel, Netlify, Next.js, Apache .htaccess, and Nginx from source and destination paths
Use tool ->Developer
SPF Record Generator
Generate SPF TXT records for domain email with includes, IPv4, IPv6, MX, A, and all-policy options
Use tool ->Developer
DMARC Record Generator
Generate DMARC TXT records with policy, reporting emails, alignment, percentage, and subdomain rules
Use tool ->Developer
DNS Record Generator
Generate common DNS records including A, AAAA, CNAME, TXT, MX, and SRV with copy-ready zone-style output
Use tool ->Developer
MX Record Generator
Generate MX records for business email providers with priority, host, TTL, and copy-ready DNS values
Use tool ->Developer
User Agent Parser
Parse browser, OS, device type, rendering engine, and bot hints from a user agent string
Use tool ->Firebase
Firebase Cost Calculator
Estimate Firebase costs from Firestore, Hosting, storage, and traffic usage
Use tool ->Firebase
Firebase Rules Generator
Generate starter Firestore and Storage security rules
Use tool ->Android
Android Manifest Generator
Create AndroidManifest.xml snippets with permissions and deep links
Use tool ->Android
Deep Link Generator
Generate app links, Android intent URLs, and manifest intent filters
Use tool ->Firebase
FCM Payload Builder
Build Firebase Cloud Messaging JSON payloads for tokens, topics, and conditions
Use tool ->Android
Logcat Analyzer
Analyze Android logcat output for errors, warnings, crashes, and exceptions
Use tool ->Android
APK Size Analyzer
Inspect APK file size by category and largest ZIP entries
Use tool ->Android
Play Store Release Notes Generator
Generate Google Play release notes under the 500-character limit
Use tool ->Developer
Bug Report Template Generator
Create clear bug reports with steps to reproduce, expected result, actual result, environment, and severity
Use tool ->Developer
Release Checklist Generator
Create a software release checklist for QA, backups, analytics, deployment, rollback, and post-launch checks
Use tool ->Developer
API Requirements Template
Draft API requirements with endpoints, auth, payloads, errors, rate limits, webhooks, and testing notes
Use tool ->Developer
Beta Testing Checklist
Create a beta testing checklist for devices, testers, builds, install links, feedback, and release readiness
Use tool ->Developer
Test Case Generator
Generate practical test cases with scenario, steps, expected result, priority, device, and owner
Use tool ->Developer
App Feedback Form Builder
Build a tester feedback form for mobile apps with device, build, rating, bug, screenshot, and suggestion fields
Use tool ->Developer
App Store Listing Checklist
Create an app store listing checklist for title, screenshots, privacy, category, keywords, and release notes
Use tool ->Developer
Crash Report Summary Template
Summarize crash reports with device, app version, frequency, stack trace, impact, and next debugging step
Use tool ->Developer
Tester Invite Message Generator
Write clear beta tester invite messages with install link, QR note, testing scope, deadline, and feedback instructions
Use tool ->Developer
QA Device Matrix Generator
Plan mobile QA coverage by device, OS, screen size, network, priority, owner, and testing notes
Use tool ->Developer
Build Handoff Checklist
Create a mobile build handoff checklist with version, environment, install link, release notes, risks, and owners
Use tool ->Developer
App Version Name Generator
Generate practical app version names, build numbers, release labels, and changelog headings
Use tool ->Developer
iOS Provisioning Checklist
Create an iOS provisioning checklist for UDIDs, bundle ID, certificates, profiles, entitlements, and install issues
Use tool ->Developer
Store Review Response Template
Draft factual App Store or Play Store review responses, rejection replies, and policy clarification notes
Use tool ->Developer
Privacy Data Safety Checklist
Prepare app privacy, data safety, SDK, permission, and account deletion checks before store submission
Use tool ->Developer
Phased Rollout Planner
Plan staged app rollout percentages, monitoring metrics, release gates, and rollback triggers
Use tool ->Developer
UAT Sign-off Template
Create a clean user acceptance testing sign-off note with scope, tested flows, issues, and approval status
Use tool ->Developer
Mobile App Test Plan Generator
Generate a mobile app QA test plan for platforms, devices, flows, regression, smoke testing, and UAT
Use tool ->Developer
API Integration Checklist
Plan API integrations with auth, endpoints, payloads, rate limits, errors, webhooks, sandbox, and production checks
Use tool ->Developer
Payment Gateway Integration Checklist
Prepare payment gateway integration checks for checkout, webhooks, refunds, security, reconciliation, and go-live
Use tool ->Developer
Website Launch QA Checklist
Create a website launch QA checklist for SEO, forms, analytics, redirects, performance, security, and mobile testing
Use tool ->Developer
Post-Launch Support Checklist
Plan post-launch support checks for monitoring, incidents, analytics, feedback, bug fixing, and handover
Use tool ->Developer
Bug Triage Matrix
Prioritize bugs by severity, impact, frequency, workaround, owner, and release decision
Use tool ->Developer
Release Announcement Template
Write release announcements with what changed, who benefits, action needed, rollout notes, and support links
Use tool ->