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)
Inflation Calculator - CPI Dollar Adjuster
Adjust any dollar amount for real US inflation with official monthly CPI-U data since 1913. Shows exact indexes used. 100% private.
NewInvestment Calculator - Stock Profit & Portfolio Tracker
Free investment calculator with portfolio tracker. Calculate stock profit, ROI, dividend yield, and cost basis. No signup, 100% private.
NewIP Address Lookup - Find Your IP Address
Free IP address lookup tool. Find your public IP, location, ISP, and geolocation data instantly. No signup required.
Is It Down? - Website Down Checker
Free website down checker. Check if any site is down for everyone or just you. Real-time HTTP status, response time. No signup. AI cannot check real-time website status - we do.
NewJavaScript Obfuscator - Protect JS Code Online
Free online JavaScript obfuscator. Protect JS source code with variable renaming, string encryption, control flow flattening, dead code injection, debug protection, and self-defending. 100% private browser, no signup. AI cannot reliably obfuscate JS - we use a deterministic engine.
NewJS Formatter & Beautifier - JavaScript Code Beautify Online
Free JavaScript formatter and beautifier. Beautify messy JS, minify for production, validate syntax. No signup, 100% private browser processing. AI cannot format code - we use deterministic js-beautify engine.
NewJSON Diff - Compare JSON Documents Online
Free JSON diff tool. Compare two JSON documents and see differences instantly. Highlights added, removed, and modified values. 100% private.
NewJSON Formatter - Format & Validate JSON
Free JSON formatter. Format, minify, beautify JSON and convert to YAML with syntax error detection.
PopularJSON Schema Validator - Validate JSON Against Schema Online
Free JSON Schema validator. Validate JSON data against Draft-07, 2019-09, and 2020-12 schemas. Detailed error paths with JSON Pointer, all-errors mode, 100% private browser. AI cannot validate JSON against schema - we do.
NewJSON 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.
NewJSON to TypeScript Converter - Free Online Type Generator
Free JSON to TypeScript converter. Generate TypeScript interfaces, types, and Zod schemas from any JSON. 100% private browser tool. No upload, no signup.
NewJSON to XML Converter - Free Bidirectional Online Tool
Free JSON to XML converter and XML to JSON. Bidirectional with attribute handling, root element control, indentation options, and syntax validation. 100% private, no upload, no signup. AI cannot convert between JSON and XML reliably - we do.
NewJSON to YAML Converter - Free Bidirectional Tool
Free JSON to YAML converter and YAML to JSON. Bidirectional with indentation control, key sorting, syntax validation. 100% private, no upload, no signup.
NewJWT Decoder - Decode & Verify Tokens
Free JWT decoder and token inspector. Decode JSON Web Tokens, inspect claims, verify payload data and JWT format. 100% browser-based, no signup.
JWT Generator - Create Signed Tokens Online
Free JWT generator. Create signed JSON Web Tokens with HS256, HS384, HS512 algorithms using Web Crypto API. No signup, no upload, 100% private browser processing. AI cannot generate valid signed JWTs - we do.
NewKeyboard Tester - Test All Keys Online Free
Free online keyboard tester. Press each key to verify it works. Detect stuck keys, ghosting, rollover. QWERTY, AZERTY, QWERTZ, Dvorak, Colemak. No signup.
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.
NewLoan Calculator - Mortgage & Extra Payment Optimizer
Free loan calculator that shows more than just your payment. See how extra payments save thousands, when PMI drops, and when you own your home free.
Lorem Ipsum Generator - Free Placeholder Text
Free Lorem Ipsum generator for designers and developers. Generate placeholder text by paragraphs, sentences, or words. Start with classic Lorem ipsum or randomized. No signup, browser-based.
NewMermaid Diagram Generator - Free Flowchart & Diagram Maker
Free online Mermaid diagram generator. Create flowcharts, sequence diagrams, class diagrams, ER diagrams, Gantt charts from text. Live preview, SVG/PNG export. No signup, 100% private browser processing. AI cannot render diagrams - we do.
NewMeta Tag Generator - Free SEO Tool
Free SEO meta tag generator. Create title tags, meta descriptions, OG, and Twitter Cards with live SERP preview. Character counting, copy HTML. No signup.
NewMicrophone Test - Free Online Mic Tester & Audio Checker
Free online microphone test. Measure mic levels, detect clipping and noise, play back your voice, get a verdict and report. No signup, 100% private.
NewMileage Calculator - IRS Tax Deduction Tracker Free
Free mileage calculator with IRS tax deduction tracker. Auto-handles 2026 mid-year rate. Business, medical, moving, charity. CSV export, 100% private.
NewMock Data Generator - Free Fake Test Data Online
Free mock data generator. Generate realistic fake test data as JSON, CSV, or SQL. Presets for users, products, companies, addresses, blog posts, transactions. No signup, 100% private browser tool. AI cannot generate consistent test data - we do.
NewMonitor Test - Dead Pixel & Refresh Rate Tester Online
Free online monitor test. Full-screen patterns find dead pixels, stuck pixels, backlight bleed, banding, ghosting and geometry faults. Measure the real refresh rate in Hz, guided wizard, exportable report. No signup, 100% private.
NewMorse Code Translator - Encode/Decode Morse Code
Free Morse code translator. Encode text to Morse code and decode Morse back to text. Instant conversion, audio playback, and copy functionality.
Mortgage Calculator with PMI, Tax & Insurance
Free mortgage calculator with PMI, property tax, insurance, HOA. Shows true monthly payment, total cost, amortization schedule, and affordability.
NewMouse Tester - Test Mouse Buttons Online Free
Free online mouse tester. Test every button, detect double-click chatter, scroll faults, polling rate and movement. Export a report. No signup.
NewNumber to Words Converter - Spell Out Numbers in English
Free number to words converter. Convert any number to English words for checks, invoices, legal docs. Supports decimals, currency, lakh/crore. 100% accurate. No signup.
NewOn This Day in History - Historical Events & Famous Births
Discover what happened on this day in history. Free database of major historical events, famous births, notable deaths, and holidays. Updated daily. No signup.
NewOnline Chart Maker - Bar, Line, Pie & Radar
Free online chart maker and graph generator. Create bar, line, pie, doughnut, and radar charts with customizable colors and data. Export PNG. No signup, 100% private browser processing. AI cannot draw accurate charts - we do.
NewOnline Code Runner - Free Python JS HTML IDE
Free online code runner. Real Python via Pyodide, sandboxed JavaScript Web Worker, live HTML preview. No signup. AI cannot execute your code - we do.
NewOnline Guitar Tuner - Free Mic Guitar Tuner
Free online guitar tuner. Tune by microphone with real-time pitch detection and cent-precision needle. 8 tunings plus Bass, Ukulele, Violin. 100% private.
NewOnline Metronome - Free BPM Beat & Practice Tool
Free online metronome with tap tempo, time signatures, subdivisions, and visual beat indicator. Practice with precision timing for any instrument. 100% browser-based, no signup.
NewP-Value Calculator - Hypothesis Test & Z, T, Chi-Square
Free p-value calculator. Run z-test, t-test (one/two-sample/paired), chi-square, linear regression and confidence interval. Exact p-values, step-by-step. No signup, 100% private.
NewPassport Photo Maker - Free Online 2x2, 35x45mm, 35x35mm
Free online passport photo maker. Create compliant US 2x2, Schengen/UK 35x45mm, India 35x35mm, China 33x48mm photos. Auto white background, print sheet (4x6/A4), 100% private browser processing.
NewPassword Generator - Create Strong Passwords
Generate strong, secure passwords with real-time strength analysis. Learn what makes a password secure.
PopularPassword Strength Checker - Analyze & Test Password Security
Free online password strength checker with entropy, crack time estimation for 3 scenarios, character analysis, and breach check via HIBP k-anonymity. 100% private browser. No signup.
NewPDF Aloud Reader - Read PDF Aloud Free
Free PDF aloud reader. Listen to any PDF in your browser with natural voices. Auto-scroll, bookmark, search. 100% private, no upload.
NewPDF Compressor - Free Online File Size Reducer
Free PDF compressor with 4 levels (light, medium, strong, aggressive). 100% private browser processing, no upload, no signup, no daily limit, no watermark. AI cannot process binary PDFs.
NewPDF Editor - Edit, Rotate, Delete, Annotate PDF Pages
Free online PDF editor. Rotate, delete, reorder pages, add text annotations, crop, and extract pages. No upload required - works entirely in your browser.
PDF Merger - Combine Multiple PDFs into One
Free online PDF merger. Combine multiple PDF files into one with drag-drop reordering, visual preview, and compression. No upload limit. Works in browser.
PDF Page Numbers - Add Page Numbers to PDF Free Online
Free PDF page number adder. Add page numbers to any PDF - Arabic or Roman format, 9 positions, custom prefix, skip cover. 100% private, no upload.
NewPDF Redactor - Permanently Redact PDF Online Free
Free PDF redactor. Search-and-redact text, draw boxes, auto-detect emails, phones, credit cards, SSN. 100% client-side. AI cannot redact binary PDFs.
NewPDF Signer - Sign PDF Online Free Electronic Signature
Free PDF signer. Draw electronic signature, place on any PDF page, add printed name + date. 100% private browser, no upload, no signup, no watermark.
NewPDF to Excel Converter - Free Online PDF to XLSX
Free online PDF to Excel converter. Extract tables and data from PDF to XLSX or CSV. Smart position-based table detection, multi-page support, editable preview. 100% private, no upload, no signup, unlimited, no watermark. AI cannot parse binary PDFs or generate valid XLSX files - this real pipeline does.
NewPDF to Image Converter - Free Online JPG PNG WebP
Free PDF to image converter. Convert PDF pages to JPG, PNG, or WebP. Choose DPI (72-300), quality, page range. Preview thumbnails, 100% private browser processing, no upload, no signup, no watermark.
NewPDF to Word Converter - Free DOCX Online
Free PDF to Word converter. Extract text from PDF to editable DOCX, RTF, or TXT. 100% private browser processing, no upload, no signup, no daily limit, no watermark. AI cannot generate valid .docx files.
NewPDF Unlocker - Remove Password Online Free
Free online PDF unlocker. Remove password protection from PDF files entirely in your browser. AES-128/256, no upload, no signup, no daily limits. 100% private. AI cannot unlock encrypted PDFs - we do.
NewPDF Watermark - Add Text Watermark to PDF Free Online
Free online PDF watermark tool. Add CONFIDENTIAL, DRAFT, or custom text watermarks. Full control over font, size, color, opacity, rotation, position & tile mode. 100% private, no upload, no signup.
NewFrequently 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.