Developer tools that work.
245 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 245 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.
NewAge 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 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 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. Video generation rate-limited to 1/min.
NewAI Video Generator - Text to Video Free No Signup
Free AI video generator. Turn text prompts into MP4 videos with Agnes AI. 4 aspect ratios, 2-5s durations, image-to-video. No signup, no watermark, no daily limit.
NewAnagram 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.
NewAspect 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 media presets for YouTube, Instagram, TikTok, Twitter. 100% private.
NewAstronomy 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 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 vehicle price, down payment, trade-in, sales tax, APR, and loan term. Compare 24-84 month terms with full amortization schedule. No signup, 100% private browser tool.
NewBackground 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. AI cannot scan barcodes - we do.
NewBase64 Encoder/Decoder - Encode Data
Free online Base64 encoder and decoder. Encode text to Base64 or decode Base64 back to plain text instantly in your browser. Private, no upload, no signup.
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.
NewCalorie 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.
NewChess 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.
NewCode 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 source code into beautiful syntax-highlighted PNG images. 7 themes, padding, fonts, window frame, transparent background. 100% private, no upload.
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.
NewColor Contrast Checker - WCAG AA AAA Accessibility Checker
Free WCAG color contrast checker. Check AA and AAA accessibility for text and background colors. Real-time ratio, live preview, pass/fail results. No signup.
NewColor 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
Free online color picker. Pick colors and convert between HEX, RGB, and HSL formats with live color preview and instant copy. No signup required, 100% free.
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, 100% private browser tool. AI cannot compute compound interest accurately - we do.
NewConnections 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 - Access-Control-Allow-Origin Headers
Free CORS header generator. Configure allowed origins, methods, headers, credentials. Generate Nginx, Apache, Express, Flask, Cloudflare Workers snippets. Preflight simulation. AI gets CORS wrong - we don't.
NewCover Letter Generator - Free AI Builder
Free AI cover letter generator. Professional, ATS-friendly letters in seconds. 4 tones, 3 templates, download TXT. No signup, unlimited.
NewCron Generator - Create Cron Expressions
Generate cron expressions interactively. Pick minute, hour, day, month and weekday, then see the next execution times. Copy a crontab line instantly.
Cryptocurrency Price Tracker - Live Crypto Prices & Charts
Free crypto price tracker with live prices for 17,000+ coins and 24h changes. AI chatbots cannot show real-time prices - get live market data here.
CSS Animation Generator - Keyframe Animations with Live Preview
Free CSS animation generator with 15 presets, custom keyframes, and live preview. Create @keyframes animations visually. Copy CSS. No signup, 100% browser-based. AI cannot show animations - we can.
NewCSS Box Shadow Generator - Live Preview & Depth Presets
Free CSS box shadow generator. Multi-layer shadows, depth presets, inset toggle, live preview. Copy production-ready CSS. No signup, 100% browser-based.
NewCSS Filter Generator - Visual CSS Filter Builder
Free CSS filter generator. Visually create and customize CSS filter effects for images and elements. 10 filter functions (blur, brightness, contrast, grayscale, sepia, hue-rotate, invert, saturate, opacity, drop-shadow), 8 presets, before/after comparison, live preview. Copy production-ready CSS. No signup, 100% browser-based. AI cannot render CSS filter effects visually - we do.
NewCSS Flexbox Generator - Visual Flex Layout Builder with Live Preview
Free CSS flexbox generator with interactive visual builder. Tune direction, wrap, justify-content, align-items, gap, and per-item flex (grow/shrink/basis/order/align-self). 7 presets. Copy CSS/HTML. No signup, 100% browser-based. AI cannot show you interactive flexbox layouts - we do.
NewCSS Formatter & Validator - Beautify & Minify CSS Online
Free online CSS formatter and validator. Beautify messy CSS, minify for production, fix syntax errors. Instant results, no signup required.
CSS Gradient Generator - Linear, Radial & Conic Gradients
Free CSS gradient generator. Create beautiful linear, radial, and conic CSS gradients with live preview, angle dial, and multiple color stops. Copy CSS code or export SVG. No signup, 100% free.
NewCSS Grid Generator - Visual Grid Layout Builder with Live Preview
Free CSS grid generator with interactive visual builder. Define columns, rows, gaps, and alignment. Preset layouts like Holy Grail, Photo Gallery, Dashboard. Copy CSS/HTML. No signup, 100% browser-based. AI cannot show you interactive grid layouts - we do.
NewCSS to Tailwind Converter - Free Online CSS to Utility Classes
Free CSS to Tailwind converter. Convert any CSS properties to Tailwind utility classes instantly. Supports 100+ properties including layout, flexbox, grid, typography, colors, borders. No signup, 100% private browser processing.
NewcURL to Code Converter - Python, Node, Go, PHP, C#
Convert curl commands to Python, Node, Go, PHP, C# code. Deterministic parser, 100% in-browser, no upload, no signup.
NewDate Calculator - Days Between & Date Arithmetic
Free online date calculator. Calculate days between dates, add subtract days/weeks/months/years, count business days. 100% private browser processing. AI hallucinates date math - we deliver deterministic results.
NewDays Until Calculator - Countdown to Any Date
Free days until calculator. Countdown to any date: Christmas, birthday, holiday, or event. See how many days, hours, minutes left. No signup required.
DNS & WHOIS Lookup - Check Domain Records
Free DNS lookup and WHOIS checker. Query DNS records (A, AAAA, MX, NS, SOA, TXT) and domain registration info instantly. No signup required.
Dog Age Calculator - Dog Years to Human Years
Free dog age calculator. Convert dog years to human years with size-adjusted AVMA formulas and the UCSD epigenetic clock. Breed presets, life stages, chart. No signup, 100% private.
NewDomain Age Checker - Free WHOIS Domain Age Lookup
Free domain age checker. Check how old any domain is with instant WHOIS lookup. See creation date, age in years/months/days, expiry date, registrar, and nameservers. No signup. AI cannot check real WHOIS records - we do.
NewDrawing Board - Free Online Whiteboard & Sketch Pad
Free online drawing board. Sketch, draw shapes, add text, save as PNG. No signup, no upload, 100% private browser canvas tool. AI cannot draw - you do it yourself.
NewDue Date Calculator - Pregnancy & Ovulation Calendar
Free due date calculator using LMP, conception, and IVF methods. Includes ovulation calculator and period predictor. 100% private, no signup, no tracking. AI cannot compute personalized due dates - we use deterministic formulas.
NewEmail Authentication Checker - SPF DKIM DMARC Check
Free email authentication checker. Check SPF, DKIM, and DMARC records for any domain. Fix email deliverability. AI cannot check real DNS records - we do.
NewEmail Verifier - Verify Email Addresses Instantly
Free email verifier. Check if email addresses are valid and can receive messages. Detect disposable emails and SMTP issues. No signup required.
Excel to PDF Converter - Free Online XLSX to PDF
Free online Excel to PDF converter. Convert XLSX and XLS to PDF in your browser. Multi-sheet support. 100% private, no upload, no signup, unlimited conversions. AI cannot convert binary Excel files - we do.
NewFrequently Asked Questions
Are all 245 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?
No. 245 out of 245 tools process everything in your browser. Only 3 tools (AI Chat, AI Detector, Image Generator, Story Animator) call a server API because the underlying model requires GPU compute — and those calls send no logs.
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 245 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.