Developer Tools

A collection of privacy-first, client-side tools for software engineers. Decode, format, and debug without your data ever leaving the browser.

JSON Formatter + Validator
Format, beautify, and deep-validate JSON syntax with line pointers.
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JSON ↠- CSV ↠- XML
Multi-way data converter for JSON, CSV, and XML formats.
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SQL Formatter
Beautify and clean up messy SQL queries for multiple dialects.
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Cron Expression Builder
Build and parse complex cron schedules with a visual interface.
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Regex Tester
Test Regular Expressions with real-time explanation and matching.
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JWT Decoder
Safely decode JWTs locally with claim explanations and metadata.
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URL Encoder / Decoder
Safely encode special characters for URLs or decode a URI component.
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Text Diff Checker
Compare two pieces of text side-by-side and highlight differences.
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CSS Unit Converter
Convert between pixels, rem, em, and viewport units instantly.
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UUID Generator
Bulk generate cryptographically secure Version 4 UUIDs.
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Base64 & Image Tool
Encode/decode text and images to Base64 Data URIs.
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IP Subnet Calculator
Professional CIDR tool for network range and host capacity.
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Time Zone Pro
Coordinate meetings with IST-focused presets for remote teams.
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Bandwidth Estimator
Calculate file transfer times and Mbps vs MB/s conversion.
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Curl to Code
Instantly convert curl commands to Python, JS, Go, and more.
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Aes Encrypt Decrypt
Free high-precision, offline-first client-side Aes Encrypt Decrypt tools with dynamic sliders and calculations.
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Api Cost Estimator
Free high-precision, offline-first client-side Api Cost Estimator tools with dynamic sliders and calculations.
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Code Diff Viewer
Free high-precision, offline-first client-side Code Diff Viewer tools with dynamic sliders and calculations.
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Nginx Config Generator
Instantly generate high-performance, secure Nginx virtual host configuration blocks.
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Rss Feed Validator
Free high-precision, offline-first client-side Rss Feed Validator tools with dynamic sliders and calculations.
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Git Commit Linter
Free high-precision, offline-first client-side Git Commit Linter tools with dynamic sliders and calculations.
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Csv To Sql Insert
Free high-precision, offline-first client-side Csv To Sql Insert tools with dynamic sliders and calculations.
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Csv Null Value Handler
Free high-precision, offline-first client-side Csv Null Value Handler tools with dynamic sliders and calculations.
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Package Json Validator
Free high-precision, offline-first client-side Package Json Validator tools with dynamic sliders and calculations.
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Html Validator
Free high-precision, offline-first client-side Html Validator tools with dynamic sliders and calculations.
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Css Specificity Calculator
Free high-precision, offline-first client-side Css Specificity tools with dynamic sliders and calculations.
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Csv Data Type Converter
Free high-precision, offline-first client-side Csv Data Type Converter tools with dynamic sliders and calculations.
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Glassmorphism CSS Generator
Design and preview ultra-premium glassmorphism UI cards with real-time CSS backdrop-filter export.
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Graphql Query Formatter
Free high-precision, offline-first client-side Graphql Query Formatter tools with dynamic sliders and calculations.
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Ab Test Calculator
Free high-precision, offline-first client-side Ab Test tools with dynamic sliders and calculations.
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Box Shadow Generator
Free high-precision, offline-first client-side Box Shadow tools with dynamic sliders and calculations.
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Breadcrumb Schema Generator
Free high-precision, offline-first client-side Breadcrumb Schema tools with dynamic sliders and calculations.
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Character Encoding Converter
Free high-precision, offline-first client-side Character Encoding Converter tools with dynamic sliders and calculations.
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Cidr Calculator
Free high-precision, offline-first client-side Cidr tools with dynamic sliders and calculations.
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Color Palette Generator
Free high-precision, offline-first client-side Color Palette tools with dynamic sliders and calculations.
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Color Shades Generator
Free high-precision, offline-first client-side Color Shades tools with dynamic sliders and calculations.
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Color Tints Generator
Free high-precision, offline-first client-side Color Tints tools with dynamic sliders and calculations.
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Csp Policy Generator
Free high-precision, offline-first client-side Csp Policy tools with dynamic sliders and calculations.
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Data Anonymizer
Free high-precision, offline-first client-side Data Anonymizer tools with dynamic sliders and calculations.
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Dataset Analyzer
Free high-precision, offline-first client-side Dataset Analyzer tools with dynamic sliders and calculations.
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Data Storage Converter
Free high-precision, offline-first client-side Data Storage Converter tools with dynamic sliders and calculations.
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Date To Timestamp
Free high-precision, offline-first client-side Date To Timestamp tools with dynamic sliders and calculations.
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Duplicate Word Remover
Free high-precision, offline-first client-side Duplicate Word Remover tools with dynamic sliders and calculations.
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Excel Data Cleaner
Free high-precision, offline-first client-side Excel Data Cleaner tools with dynamic sliders and calculations.
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Excel Sheet Merger
Free high-precision, offline-first client-side Excel Sheet Merger tools with dynamic sliders and calculations.
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Fake Address Generator
Free high-precision, offline-first client-side Fake Address tools with dynamic sliders and calculations.
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Fake Email Generator
Free high-precision, offline-first client-side Fake Email tools with dynamic sliders and calculations.
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Fake Name Generator
Free high-precision, offline-first client-side Fake Name tools with dynamic sliders and calculations.
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Fake Person Generator
Free high-precision, offline-first client-side Fake Person tools with dynamic sliders and calculations.
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Fake Phone Generator
Free high-precision, offline-first client-side Fake Phone tools with dynamic sliders and calculations.
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Faq Schema Generator
Free high-precision, offline-first client-side Faq Schema tools with dynamic sliders and calculations.
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Gitignore Generator
Free high-precision, offline-first client-side Gitignore tools with dynamic sliders and calculations.
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Google Serp Simulator
Free high-precision, offline-first client-side Google Serp Simulator tools with dynamic sliders and calculations.
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Gradient Generator
Free high-precision, offline-first client-side Gradient tools with dynamic sliders and calculations.
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Graphql Tester
Free high-precision, offline-first client-side Graphql Tester tools with dynamic sliders and calculations.
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Image Placeholder Generator
Free high-precision, offline-first client-side Image Placeholder tools with dynamic sliders and calculations.
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Image To Color Palette
Free high-precision, offline-first client-side Image To Color Palette tools with dynamic sliders and calculations.
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Large Text File Viewer
Free high-precision, offline-first client-side Large Text File Viewer tools with dynamic sliders and calculations.
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License Generator
Free high-precision, offline-first client-side License tools with dynamic sliders and calculations.
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Line Counter
Free high-precision, offline-first client-side Line Counter tools with dynamic sliders and calculations.
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Log File Analyzer
Free high-precision, offline-first client-side Log File Analyzer tools with dynamic sliders and calculations.
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Logo Placeholder Generator
Free high-precision, offline-first client-side Logo Placeholder tools with dynamic sliders and calculations.
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Markdown Table Generator
Free high-precision, offline-first client-side Markdown Table tools with dynamic sliders and calculations.
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Markdown To Slack
Free high-precision, offline-first client-side Markdown To Slack tools with dynamic sliders and calculations.
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Memorable Password Generator
Free high-precision, offline-first client-side Memorable Password tools with dynamic sliders and calculations.
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Number Base Converter
Free high-precision, offline-first client-side Number Base Converter tools with dynamic sliders and calculations.
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Oauth Pkce Generator
Free high-precision, offline-first client-side Oauth Pkce tools with dynamic sliders and calculations.
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Oauth Scope Builder
Free high-precision, offline-first client-side Oauth Scope Builder tools with dynamic sliders and calculations.
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Og Preview Tester
Free high-precision, offline-first client-side Og Preview Tester tools with dynamic sliders and calculations.
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Password Entropy Calculator
Free high-precision, offline-first client-side Password Entropy tools with dynamic sliders and calculations.
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Password Strength Checker
Free high-precision, offline-first client-side Password Strength Checker tools with dynamic sliders and calculations.
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Pin Generator
Free high-precision, offline-first client-side Pin tools with dynamic sliders and calculations.
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Product Schema Generator
Free high-precision, offline-first client-side Product Schema tools with dynamic sliders and calculations.
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Px To Rem Converter
Free high-precision, offline-first client-side Px To Rem Converter tools with dynamic sliders and calculations.
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Qr Code Generator
Free high-precision, offline-first client-side Qr Code tools with dynamic sliders and calculations.
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Random Date Generator
Free high-precision, offline-first client-side Random Date tools with dynamic sliders and calculations.
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Random Number Generator
Free high-precision, offline-first client-side Random Number tools with dynamic sliders and calculations.
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Random Time Generator
Free high-precision, offline-first client-side Random Time tools with dynamic sliders and calculations.
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Random Word Generator
Free high-precision, offline-first client-side Random Word tools with dynamic sliders and calculations.
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Rate Limit Header Parser
Free high-precision, offline-first client-side Rate Limit Header Parser tools with dynamic sliders and calculations.
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Rest Endpoint Documenter
Free high-precision, offline-first client-side Rest Endpoint Documenter tools with dynamic sliders and calculations.
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Robots Txt Generator
Free high-precision, offline-first client-side Robots Txt tools with dynamic sliders and calculations.
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Secret Scanner
Free high-precision, offline-first client-side Secret Scanner tools with dynamic sliders and calculations.
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Semver Calculator
Free high-precision, offline-first client-side Semver tools with dynamic sliders and calculations.
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String Template Tester
Free high-precision, offline-first client-side String Template Tester tools with dynamic sliders and calculations.
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Svg Optimizer
Free high-precision, offline-first client-side Svg Optimizer tools with dynamic sliders and calculations.
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Syllable Counter
Free high-precision, offline-first client-side Syllable Counter tools with dynamic sliders and calculations.
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Test Data Generator
Free high-precision, offline-first client-side Test Data tools with dynamic sliders and calculations.
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Text Cleaner
Free high-precision, offline-first client-side Text Cleaner tools with dynamic sliders and calculations.
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Text Splitter
Free high-precision, offline-first client-side Text Splitter tools with dynamic sliders and calculations.
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Time Zone Converter
Free high-precision, offline-first client-side Time Zone Converter tools with dynamic sliders and calculations.
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Timestamp To Date
Free high-precision, offline-first client-side Timestamp To Date tools with dynamic sliders and calculations.
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Trailing Space Remover
Free high-precision, offline-first client-side Trailing Space Remover tools with dynamic sliders and calculations.
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Utm Builder
Free high-precision, offline-first client-side Utm Builder tools with dynamic sliders and calculations.
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Professional-Grade Developer Utilities

Our Developer Tools hub is built for engineers who value speed and privacy. We provide a suite of tools for data formatting, security debugging, and network calculations that run entirely in your browser.

Data Manipulation & Formatting

Whether you need to beautify minified JSON, convert between CSV and XML, or format complex SQL queries, our tools handle large datasets with ease and consistency.

Testing & Debugging

Debug your Regular Expressions with our live Regex Tester, parse complex Cron schedules into human-readable text, or safely decode JSON Web Tokens (JWT) to inspect claims locally.

Why ModernCalcs for Developers?

  • Zero Backend: We don't have a server-side for these tools. Your data is 100% private.
  • Modern UI: Clean, responsive interface designed for professional productivity.
  • No Signup Required: Fast access to tools without registration or login.
  • Instant Results: Leverages local compute for lightning-fast transformations.