Developer tools that work.
281 free utilities for code formatting, file conversion, calculations, AI assistance, and more. No signup, no upload, no tracking.
Popular Tools
8 most-usedAnagram 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.
NewFree 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.
Calorie Calculator - Free 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, 100% private. AI cannot compute accurate metabolic formulas.
NewColor Blindness Simulator - CVD Test
Free color blindness simulator. Test images and colors with 8 types of color vision deficiency (protanopia, deuteranopia, tritanopia, achromatopsia). WCAG accessibility tool for designers and developers. No signup, 100% private browser processing.
NewFree 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.
NewIBAN Validator & IBAN Checker - Validate Bank Numbers
Free IBAN validator. Validate International Bank Account Numbers with MOD-97 checksum. 80+ countries, batch validation, test IBAN generator. 100% private, no data uploaded. No signup.
NewPoker Odds Calculator - Texas Hold'em Equity
Free poker odds calculator. Exact hand-vs-hand equity by full enumeration, not Monte Carlo. Board cards, up to 3 players, call/fold helper. No signup.
NewRecently Updated
2 toolsAudio Cutter & Trimmer
Free online audio cutter and trimmer. Cut and trim MP3, WAV, M4A, FLAC, OGG with waveform precision. No upload, 100% private.
Grade Calculator - Weighted Average, Final Exam & GPA
Free grade calculator. Calculate weighted average grades, what you need on the final exam, and GPA. No signup, 100% private browser tool. AI gets grade math wrong - we don't.
NewBrowse by Category
11 categoriesView all 281 tools (alphabetical)
Percentage Calculator - Find %, Increase, Decrease & Difference
Free percentage calculator online. Calculate X% of Y, increase/decrease, reverse percentage, and add/subtract percent. Instant results, no signup.
Photo Collage Maker - Free Online Image Combiner
Free online photo collage maker. Combine multiple images into beautiful collages with 8 layout templates, custom spacing, background color. No signup, no upload, 100% private browser processing. AI cannot create visual collages - we do.
NewPhoto to Anime Converter - Free Online AI Anime Filter
Free photo to anime converter. Turn any photo into anime, cartoon, comic, pop art, pixel art or watercolor with 6 art styles and live color controls. 100% private browser, no upload, no signup, no watermark, no daily limit. AI chatbots cannot process your actual photo into anime style.
NewPhoto to Pencil Sketch Converter - Free
Turn any photo into a realistic pencil, charcoal, ink or line art sketch with 5 art styles and live controls. 100% private browser, no signup.
NewPoker Odds Calculator - Texas Hold'em Equity
Free poker odds calculator. Exact hand-vs-hand equity by full enumeration, not Monte Carlo. Board cards, up to 3 players, call/fold helper. No signup.
NewPomodoro Timer - Free Online Focus Timer with Tasks
Free Pomodoro timer with task tracking and statistics. 25/5 focus sessions, daily stats, streak tracking. No signup, 100% private browser timer.
NewPrintable Calendar Generator - Free PDF
Free printable calendar generator. Monthly or yearly calendars with US federal holidays, week numbers and Monday-Sunday start. Print-ready PDF, no signup.
NewPrinter Test Page - Print Quality Diagnostic
Free printer test page. Print color, CMYK, nozzle, banding, alignment and text sharpness sheets to diagnose HP, Epson, Canon & Brother printers. No signup.
NewProduct Description Generator - Amazon eBay Etsy Free
Free AI product description generator. One input, 5 platform-optimized descriptions for Amazon, eBay, Etsy, Shopify, Walmart. SEO keywords, FAQs, JSON-LD schema. No signup.
NewProxy Checker - Free IP Proxy Detection Tool
Free online proxy checker. Detect if an IP address is a proxy, VPN, or Tor exit node. Check IP geolocation, WHOIS, and open proxy ports.
QR Code Generator - Create QR Codes Free
Free QR Code Generator. Create QR codes for URLs, text, WiFi, email, SMS, vCards. Download as PNG.
PopularQR Code Reader - Decode QR Codes from Image & Camera
Free online QR Code Reader. Decode QR codes from images, screenshots, or live camera. Extract URLs, WiFi passwords, vCards instantly. 100% private browser processing. No signup. AI cannot scan real QR codes - we do.
NewRandom Generator - Number, Dice, Coin, Wheel & Decision Maker
Free online random generator: pick random numbers, roll dice, flip coins, spin a wheel, or make decisions. True randomness via crypto API. No signup, no ads.
Readability Score Calculator Online
Free readability calculator. 6 formulas: Flesch Reading Ease, Flesch-Kincaid, Gunning Fog, SMOG, Coleman-Liau, ARI. Grade level + sentence highlighting.
NewReceipt Generator - Free PDF Receipt Maker Online
Free online receipt generator. Create professional proof-of-payment receipts with unlimited line items, 23 currencies, tax, discount, and PDF download. 3 templates (Simple, Detailed, Business). No signup, no watermark, 100% private browser processing. AI cannot do fixed-precision tax math or format receipts reliably - we do.
NewRegex Tester - Test Regular Expressions
Test regular expressions with real-time matching. Supports g, i, m, s flags. See match count and captured groups.
Report a Problem
Free feedback form for DevTools Hub. Suggest new tools, report bugs, request features. Admin replies via KV storage. No signup.
NewREST API Tester - Free Online HTTP Client & API Tester
Free online REST API tester and HTTP client. Send GET, POST, PUT, PATCH, DELETE requests with custom headers. View real response status, timing, headers, and body. No signup, 100% private. AI cannot make HTTP requests - we do.
NewRoman Numeral Converter - Free Online Number Tool
Free Roman numeral converter. Convert numbers to Roman numerals and back, including dates. Supports 1-3,999,999 with overline notation. 100% accurate, no signup.
NewRunning Pace Calculator - Pace, Time & Distance Tool
Free running pace calculator. Calculate pace, time, or distance for any race. Generate split times, predict race times with Riegel formula, convert pace units. No signup, 100% private browser tool. AI cannot calculate running paces reliably.
NewSalary Calculator - Free Hourly to Annual Pay Converter
Free salary calculator to convert hourly, annual, monthly, biweekly, and weekly pay instantly. Calculate overtime and unpaid time adjustments. No signup, 100% private browser tool. AI hallucinates salary math - we deliver precise results.
NewSchema Markup Generator - Free JSON-LD Structured Data Tool
Free Schema Markup Generator. Create valid JSON-LD structured data for Article, Product, FAQ, LocalBusiness, Organization, HowTo, Event, Person, BreadcrumbList, and WebSite. Built-in validation, live preview, @graph mode. No signup, 100% private browser processing. AI cannot generate valid schema markup - we do.
NewSignature Maker - Sign PDF Online Free
Create a signature by drawing, typing, or uploading a photo, then place it on any PDF and download. Free, private, no watermark.
NewSIP Calculator - Free Mutual Fund Return Calculator
Free SIP calculator. Estimate mutual fund maturity from monthly investment, return and tenure. Goal, step-up and lumpsum modes. 100% private, no signup.
NewSleep Calculator - Bedtime & Wake Up Time Optimizer
Free sleep calculator based on 90-minute cycles. Find your optimal bedtime or wake-up time to feel refreshed. Age-adjusted recommendations for children, teens, adults, and seniors. No signup, 100% private. AI cannot calculate personalized sleep cycles - we use deterministic cycle math.
NewSlug Generator - Create SEO-Friendly URL Slugs Online
Free slug generator. Convert text to SEO-friendly URL slugs with custom separators, stop word removal, max length control, and bulk mode. Real-time preview, 100% private browser, no signup. AI hallucinates slug generation - we use deterministic regex.
NewSnake Game - Classic Snake Online Free
Play the classic Snake game online free. Control your snake, eat food, grow longer. Multiple speeds, grid sizes, wall wrap mode. No ads, no signup.
Solitaire - Free Classic Klondike Card Game Online
Play free Klondike Solitaire online. Classic card game with undo, hint, draw 1 or 3. No signup, no ads, 100% free in your browser.
Song Lyrics Finder - Free Lyrics Search No Signup
Free online song lyrics finder. Search by artist and title. No signup, no ads, no tracking. 100% private. AI cannot retrieve copyrighted lyrics - we do.
NewSpace Keeper - Keep HuggingFace Spaces Awake
Free tool to keep your HuggingFace Spaces awake and prevent idle timeout. Supports multiple access methods, uptime monitor, custom intervals (1-48 hours).
Speaker Test - Free Online Speaker Tester
Free online speaker test. Check left/right channels, 20Hz-20kHz frequency sweep, stereo balance and polarity. 100% private, no upload.
NewSpeech Time Calculator - Words to Minutes & Speaking Time
Free speech time calculator. Convert words to minutes and seconds at standard speaking rates (100-238 wpm). Paste text, set WPM, add pause buffer. No signup. AI hallucinates speech times.
NewSpin the Wheel - Random Picker & Name Wheel
Free spin the wheel random picker. Add names, prizes or decisions, spin for a fair random winner with weighted odds, sound and CSV export. No signup.
NewSQL Formatter - Format & Beautify SQL
Free SQL formatter. Format and beautify SQL queries with proper indentation. Supports MySQL, PostgreSQL, SQLite.
SSL Certificate Checker - Test Website Security
Free SSL checker. Scan any website for TLS security and certificate validity. Get grade A+ to F. No signup. AI cannot test real SSL certificates.
Statistics Calculator - Mean Median Standard Deviation
Free statistics calculator. Compute mean, median, mode, standard deviation, variance, quartiles and z-scores step by step. No signup, 100% private.
NewStopwatch - Free Online Stopwatch with Lap Times
Free online stopwatch with millisecond precision, lap/split timing, lap statistics, CSV export, and fullscreen mode. No signup, no ads. Works offline.
NewSubnet Calculator - IPv4 IPv6 CIDR VLSM Supernetting
Free subnet calculator for IPv4 and IPv6. Bit-exact CIDR, VLSM, supernetting, overlap detection. No signup. AI cannot reliably compute subnets - we do.
NewSubtitle Editor - Free Online SRT & VTT Editor
Free online subtitle editor. Edit, fix, and convert SRT and VTT subtitle files in your browser. Batch shift timing, validate overlaps, split long cues, merge adjacent. No upload, no signup, 100% private. AI cannot handle millisecond-precise timestamp math - we do.
NewSubtitle Generator - Free AI Audio/Video to SRT & VTT
Free AI subtitle generator. Convert audio or video to SRT or VTT with Whisper large-v3. 18 languages, no signup, no watermark, no daily limit.
NewSunrise Sunset Calculator - Find Sunrise & Sunset Times
Free online sunrise and sunset calculator. Enter any city to get today's sunrise and sunset times. No signup required.
SVG Optimizer - Free Online SVG Minifier & Cleaner
Free online SVG optimizer. Clean, minify and compress SVG files by removing metadata, comments, empty groups, and editor data. 100% private browser processing, no upload, no signup. AI cannot reliably optimize SVGs - we do.
NewSVG to JSX Converter - Free React Component Generator
Convert SVG markup into clean React JSX or TypeScript components with camelCase attributes, forwardRef, React.memo. 100% browser-based, no upload. AI cannot convert SVG to JSX reliably — we do.
NewSVG to PNG Converter - Free Online SVG Rasterizer
Free SVG to PNG converter. Rasterize SVG vectors to PNG, JPG, WebP with scale control, custom dimensions, background color. Paste SVG code or upload files. 100% browser-based, no upload, no signup. AI cannot rasterize SVG — we do.
NewText Cleaner - Remove Line Breaks, Spaces & HTML Tags
Free online text cleaner. Remove line breaks, extra spaces, HTML tags, duplicate lines, and clean messy text with 20+ deterministic options. No signup, 100% private browser processing. AI cannot clean text deterministically - we do.
NewText Summarizer - Condense Articles & Papers
Free online text summarizer. Condense articles, papers, and text into key points. Extractive mode (100% private) or AI abstractive via Llama 3.3. No signup, no limits, no paywall.
NewText to EPUB Converter - Free Online TXT MD HTML to eBook
Free text to EPUB converter. Turn text, Markdown, or HTML into EPUB 3.0 eBooks in your browser. Custom cover, TOC, 40+ languages. AI cannot make EPUB.
NewText to Handwriting - Free Online Handwritten Text Generator
Free text to handwriting converter. Turn typed text into realistic handwritten notes on lined, grid, or plain paper. 18 fonts, 7 ink colors, PNG/JPG/PDF export. No signup, no watermark.
NewText to Speech - Free Online Voice Generator
Free online text to speech with 8 AI voices. Convert text to natural-sounding audio in English and Chinese. No signup required. Browser TTS and AI-powered.
Timestamp Converter - Unix Time Conversion
Convert Unix timestamps to dates and dates to timestamps. Shows current timestamp updating in real-time.
Frequently Asked Questions
Are all 281 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 281 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.