Developer tools that work.
323 free utilities for code formatting, file conversion, calculations, AI assistance, and more. No signup, no upload, no tracking.
Popular Tools
8 most-usedFree AI Chat - No Login, No Signup
Free AI chat powered by Llama 3.3 70B. No login, no signup, no tracking. Coding, writing, math, brainstorming. Conversations stay in your browser.
NewFree Online Calculator - Math Problem Solver
Free online calculator with scientific functions, unit conversion, loan calculator, and BMI calculator. No signup required, works in any browser.
Free Email Signature Generator - Outlook Gmail HTML
Pro email signature generator. 10 table-based templates, MSO compatible, base64 photo embedding, click-to-call phones, social icons. Outlook + Gmail + Apple Mail ready. No signup, no tracking, 100% private browser tool. AI cannot produce email-client-compatible HTML.
NewImage Compressor - Reduce Image File Size Online Free
Free online image compressor. Reduce image file size without losing quality. Supports JPG, PNG, WebP. No upload, privacy-first processing.
Image Cropper - Crop Photos Free Online with Aspect Ratio Presets
Free online image cropper. Crop photos with aspect ratio presets, rotate, flip, zoom. Social media sizes for Instagram, Facebook, Twitter. No upload, 100% private browser processing. AI cannot crop your photos - we do.
NewJSON Formatter - Format & Validate JSON
Free JSON formatter. Format, minify, beautify JSON and convert to YAML with syntax error detection.
JSON to CSV Converter - Bidirectional Online Data Converter
Free JSON to CSV converter and CSV to JSON online. Flatten nested objects, auto-detect input, table preview, export file. 100% private browser processing. AI cannot convert data reliably - we do.
NewLive Sports Scores Tracker - NFL NBA MLB NHL Soccer
Free live sports scores tracker. Follow NFL, NBA, MLB, NHL and soccer in real-time. Updated every 30 seconds. No signup, no ads. AI cannot show live game scores - we do.
NewRecently Updated
6 toolsAPCA Contrast Checker - WCAG 3 Lc Calculator
Free APCA contrast checker for WCAG 3. Get the Lc value, the minimum Lc your font size and weight need, the WCAG 2.1 ratio, and a passing color fix.
NewPDF Compare - Free Online PDF Diff & Side-by-Side
Free PDF compare tool. Side-by-side visual diff with scroll sync, text-based diff with green/red highlights, page-by-page navigation, export PDF report. 100% private browser processing, no upload, no signup.
NewMath Calculator - Polynomial, Matrix, Prime Factor & More
Free math calculator. 6 modes: polynomial factoring, prime factorization, GCF/LCM, matrix (det/inv), quadratic formula, sequence. Step-by-step. No signup.
NewFree OG Image Generator - Social Card Creator 1200x630
Free OG image generator. 1200x630 Open Graph cards with multi-platform preview (Twitter, Facebook, LinkedIn, Slack). 6 templates, custom colors, fonts, logo upload. Download PNG and copy meta tags. No signup, 100% browser. AI cannot output exact OG dimensions + multi-platform safe area validation.
NewTDEE Calculator - BMR, Macro, Protein, Water, 1RM
Free TDEE calculator. 6 modes in one: BMR (3 formulas), macro split (5 diets), protein target, water intake, and 1 rep max. kg/lb toggle. No signup.
NewAI Essay Writer - Free Academic Essay Generator
Free AI essay writer for 9 types, 4 levels, 5 citation styles. Outline + thesis + draft modes, editable, downloadable. No signup, no word limit.
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11 categoriesView all 323 tools (alphabetical)
AES Encrypt Decrypt - Secure Text Online
Free AES-256-GCM encryption tool. Encrypt text with a password using PBKDF2 and Web Crypto, or decrypt it. Runs in your browser, nothing is uploaded.
Age Calculator - Years, Months, Days & Birthday
Free age calculator. Calculate your exact age in years, months, days, hours. See next birthday countdown and milestone dates. No signup required.
AI Email Writer - Free Reply Generator
Free AI email writer & reply generator. 15 email types, 6 tones, 3 lengths, 12 languages. Compose, reply, generate subject lines. No signup, no word limit.
AI Essay Writer - Free Academic Essay Generator
Free AI essay writer for 9 types, 4 levels, 5 citation styles. Outline + thesis + draft modes, editable, downloadable. No signup, no word limit.
NewAI Image Generator - Free Unlimited DALL-E 3 Flux Stable Diffusion
Free AI image generator. Create unlimited images with DALL-E 3, Flux, Stable Diffusion. No signup, no watermark, no daily limit. 100% private browser processing.
NewAI Letter Generator - 8 Types Free
Free AI letter generator for 8 real situations: thank-you, cover, apology, invitation, resignation, recommendation, complaint, congratulations. 3 tones, 5…
AI Social Media Post Generator - Free Multi-Platform
Free AI social media post generator. One input, 5 platform-optimized posts: Twitter, LinkedIn, Instagram, Facebook, TikTok. No signup, no limits, 100%…
AI Story Animator - Novel to Video with Agnes AI
Free AI story animator. Input a novel chapter, get a full storyboard with images, videos, and narration. Powered by Agnes AI multi-modal API.
AI Video Generator - Text to Video Free
Free AI video generator. Turn text prompts into videos online with Agnes AI. No signup, no watermark, no daily limit. Text to video in minutes.
Anagram Solver & Word Unscrambler - Free
Free anagram solver. Enter letters (use ? for blanks) to find every valid word from a 168K-word dictionary with Scrabble scores. No signup.
APCA Contrast Checker - WCAG 3 Lc Calculator
Free APCA contrast checker for WCAG 3. Get the Lc value, the minimum Lc your font size and weight need, the WCAG 2.1 ratio, and a passing color fix.
NewArea Calculator - Square Footage & Multi-Shape Room Area…
Free area calculator for rectangle, triangle, circle, trapezoid, L-shape rooms, multi-room aggregation. Wall area with door/window subtraction. Paint,…
ASCII Art Generator - Free Image & Text to ASCII Converter
Free ASCII art generator. Convert any image or text into ASCII art with 5 fonts, adjustable width and custom characters. PNG & TXT download, 100%…
Aspect Ratio Calculator - Free Online Tool
Free aspect ratio calculator. Calculate aspect ratio from width and height, find missing dimensions, visual preview of 16:9, 4:3, 21:9 ratios. Social…
Astronomy Calendar - Moon Phases & Meteor Showers
Free astronomy calendar with daily moon phases, sun rise/set, upcoming meteor showers, eclipses, and planetary events. Pure browser-based calculations.
NewAudio Cutter & Trimmer
Free online audio cutter and trimmer. Cut and trim MP3, WAV, M4A, FLAC, OGG with waveform precision. No upload, 100% private.
Audio Denoiser - Reduce Background Noise Free
Free audio denoiser browser tool. Remove background noise, hiss, hum, wind and ambient sound from MP3, WAV, M4A, FLAC, OGG files. 100% private, no upload,…
Audio Editor - Free Online Audio Effects & Editing Tool
Free online audio editor. Cut, fade, normalize, change speed/pitch, add reverb and echo, EQ bass/treble, reverse, trim silence. 100% private, no upload.
Audio File Transcriber - MP3 to Text Converter
Free online audio file transcriber. Convert MP3, WAV, M4A, OGG, FLAC, AAC, MP4, MOV, AVI to text with AI Whisper. Timestamps, SRT/VTT export, 25 languages.
Audio Joiner & MP3 Merger - Merge Audio Files Free
Free online audio joiner. Merge MP3, WAV, M4A, FLAC, OGG into one with drag-to-reorder, crossfade or silence gap modes. 100% private browser processing, no upload, no signup. AI cannot merge audio - we do.
NewAudio to Text Converter - Free Online Speech to Text
Free online audio to text converter. Convert speech to text in real-time with browser-based voice recognition. No uploads, no sign-up, 100% private.
Auto Loan Calculator - Free Car Payment Calculator
Free auto loan calculator. Calculate monthly car payments with tax, trade-in, down payment. Compare loan terms, total interest, amortization schedule. No…
Background Remover - Remove Image Background Free Online
Free online background remover tool. Remove image backgrounds automatically. No signup. Works with JPG, PNG, WebP. Fast and private.
Barcode Scanner - Decode EAN, UPC, Code 128, QR Codes
Free online barcode scanner. Decode EAN-13, UPC-A, Code 128, Code 39, QR codes and 15+ formats from images or camera. 100% private, no upload, no signup.…
Base64 Encoder/Decoder - Encode Data
Free Base64 encoder and decoder. Encode text to Base64 and decode back. Works entirely in your browser with no upload and no signup. 100% private.
Base64 to Image Converter - Convert Base64 String to Image
Convert base64 strings and data URIs to viewable images. Supports PNG, JPG, WebP, GIF, BMP. 100% private, browser-based, no upload required.
NewBingo Card Generator - Free Printable
Free printable bingo card generator. 1-75, 1-90, or custom themed. 100% free, no signup, no watermark, no upload. AI cannot generate cards - we do.
NewBirthday Wishes Generator - Free Personalized Messages
Free birthday wishes generator. 30+ recipient types, 6 tones, 4 output formats, multi-language. AI gives generic wishes - we personalize them. No signup,…
Body Fat Calculator - Navy, YMCA & BMI Free
Free body fat calculator: US Navy, YMCA, BMI and Jackson-Pollock methods. Fat mass, lean mass, healthy ranges and target weight. Private, no signup.
BTU Calculator - Free AC and Heating BTU Estimator
Free BTU calculator. Compute room heat load for AC and heating with ceiling, sun, insulation, climate, occupancy and kitchen factors. Convert to tons,…
Business Card Maker - Free Printable Card Designer
Free business card maker. Design cards with 5 templates, custom fonts, PNG/PDF/vCard export. No signup, 100% private. AI cannot make 300 DPI print files.
Caffeine Calculator - Half-Life Sleep Tracker
Free caffeine calculator. Personalized half-life, when to stop drinking coffee, multi-drink tracker, daily budget. NHS pregnancy safe. 100% private.
Calorie Calculator - TDEE & BMR Macro Calculator
Free calorie calculator. Calculate your TDEE, BMR, and optimal macros for weight loss, maintenance, or muscle gain. Mifflin-St Jeor equation, no signup,…
Chess Move Validator - Free Legal Move Checker Online
Free chess move validator. Play chess on an interactive board with real-time legal move validation. No signup. Perfect for learning chess rules.
NewClick Speed Test - CPS & Reaction Time
Free click speed test (CPS) and reaction tester. Measure clicks per second over 1-100 seconds, right-click, spacebar or touch. No signup, 100% private.
Code Minifier & Beautifier - JS, CSS, HTML
Free online code minifier and beautifier. Minify JS, CSS, HTML for production or beautify for debugging. Size stats, copy, all in browser. No signup.
NewCode to Image Converter - Create Beautiful Code Screenshots
Convert your source code into stunning syntax-highlighted PNG images. Choose from 7 themes, customize padding & fonts, and share beautiful code…
Color Blindness Simulator - CVD Test
Free color blindness simulator. Test how images and colors appear with 8 types of color vision deficiency (protanopia, deuteranopia, tritanopia). WCAG…
Color Contrast Checker - WCAG AA AAA
Free WCAG color contrast checker. Check if text and background colors meet AA and AAA accessibility standards. Real-time contrast ratio, pass/fail…
Color Palette Generator - Create Harmonious Color Schemes
Free color palette generator. Create harmonious schemes with 7 harmony rules. Export as CSS, Tailwind, SCSS, JSON. Lock colors, WCAG checker. No signup.
NewColor Picker - HEX RGB HSL Converter
Pick colors and convert between HEX, RGB, and HSL formats with live preview and copy buttons. Free, browser-based, 100% private.
Compound Interest Calculator - Free Investment Growth Tool
Free compound interest calculator. Calculate investment growth with monthly contributions, compounding frequency, and year-by-year breakdown. No signup,…
Concrete Calculator - Free Slab, Footing & Bag Estimator
Free concrete calculator for slabs, footings, columns, and stairs. Get cubic yards, cubic meters, bag counts (40/60/80 lb), mix ratio breakdown, and waste…
Connections Game - Free Word Puzzle Online
Play Connections word puzzle free. Group 16 words into 4 hidden categories. Unlimited puzzles, 4 difficulty levels, hints, timer. No signup, no ads, 100% free.
NewCORS Header Generator - Allow-Origin Tool
Free CORS header generator. Configure Allow-Origin, methods, headers, credentials. Generate Nginx, Apache, Express, Flask, Workers snippets.
Cover Letter Generator - Free AI Builder
Free AI cover letter generator. Create professional, ATS-friendly cover letters in seconds. 4 tones, multiple templates, download as TXT. No signup, 100%…
Cron Generator - Create Cron Expressions
Generate cron expressions interactively. Select minute, hour, day, month, weekday. See the next 10 execution times and copy to your clipboard.
Cross Stitch Pattern Maker - Free Photo to DMC Chart…
Free cross stitch pattern maker. Convert any photo to a printable DMC cross-stitch chart with thread color matching, symbols, Aida count, and PDF export.…
Cryptocurrency Price Tracker - Live Crypto Prices & Charts
Free crypto price tracker. Live prices for 17,000+ coins via CoinGecko, market cap, 24h volume, and trending list. AI cannot show real-time crypto prices.
CSS Animation Generator - Live Preview
Free CSS animation generator with live preview. Build custom @keyframes animations, 15 ready-made presets, fine-tune timing and easing, and copy CSS.
Frequently Asked Questions
Are all 323 developer tools really free?
Yes — every tool on DevTools Hub is 100% free with no signup, no trial, no daily limit, and no watermark. The site is supported by optional cloud functions and ad-free by design.
Do you upload my data to a server?
Most tools process everything in your browser. Only AI-backed tools (AI Chat, AI Detector, Image Generator, Story Animator, Translator, Paraphrasing Tool, Plagiarism Checker, Resume Builder, Cover Letter Generator, Citation Generator, ATS Resume Checker, AI Humanizer, Text-to-Speech, Text-to-Video, Text Summarizer, Math Solver, Grammar Checker, Subtitle Generator, and a few others) call a server API for GPU compute. Uploads are transient and never logged. Each tool page documents exactly what leaves your device.
Why use these tools instead of asking an AI chatbot?
AI chatbots hallucinate exact arithmetic, produce invalid JSON/XML, drop SVG attributes, and cannot compute dates, fractions, or compound interest reliably. DevTools Hub uses deterministic code — same input always yields the same verified output.
Do I need to create an account?
No account, no email, no tracking cookies. Open any tool, use it, close the tab. Your inputs never leave your browser unless you explicitly call a cloud-backed AI tool.
How often are new tools added?
New tools ship 2-3 times per week. The homepage shows a 323 tool count that updates automatically as new entries are added to the public manifest. See the sitemap.xml for the complete list.
Can I use these tools commercially?
Yes. The outputs you generate belong to you — use them in client work, internal tools, or commercial products without attribution. The tool code itself is MIT-licensed on GitHub.