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)
Retirement Calculator - 401k IRA Nest Egg
Free retirement calculator. Project nest egg with employer match and inflation. Required corpus, 4 percent rule, Social Security break-even 62/67/70.
Roman 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.
NewRoofing Calculator - Pitch Squares Shingle Bundles Free
Free roofing calculator. True roof area from pitch multiplier (1/12 to 18/12), squares, shingle bundles, underlayment, starter strip, ridge cap, drip edge…
Running Pace Calculator - Free Online Pace, Time & Distance…
Free running pace calculator. Calculate pace, time, or distance for any race. Generate splits, predict race times with Riegel formula, convert pace units.…
Salary Calculator - Free Online Hourly to Annual Converter
Free salary calculator. Convert hourly to annual, monthly, biweekly, weekly pay instantly. Calculate overtime and unpaid time adjustments. No signup, 100%…
Schema Markup Generator - Free JSON-LD Structured Data Tool
Free online Schema Markup Generator. Create valid JSON-LD structured data for Article, Product, FAQ, LocalBusiness, Organization, and more. Built-in…
Signature Maker - Sign PDF Online Free
Free signature maker. Draw, type, or upload your signature, then place it on any PDF and download. No signup, no watermark, 100% private.
SIP Calculator - Free Mutual Fund Returns
Free SIP calculator. Estimate mutual fund maturity from monthly investment, return and tenure. Goal, step-up and lumpsum modes. 100% private, no signup.
Size Converter - Shoe, Ring & Apparel Sizes
Free online size converter for shoe, ring, bra, clothing. 9-country systems + sister-size bra calculator. ISO 9407 + 8655. 100% private.
NewSleep Calculator - Optimal Bedtime & Wake Up Time
Free sleep calculator. Find your ideal bedtime or wake-up time based on 90-minute sleep cycles. Wake up refreshed, not groggy. No signup, 100% private…
Slug 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, and bulk mode. Real-time preview, no…
Snake 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.
Speech 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 pauses. No signup.
Spin the Wheel - Random Picker & Name Wheel
Free spin the wheel random picker. Add names, decisions or prizes, spin for a fair random winner with weighted odds, sound and CSV export. No signup.
SQL 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 & SD
Free statistics calculator. Compute mean, median, mode, standard deviation, variance, quartiles and z-scores step by step. No signup, 100% private.
Stopwatch - 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.
NewStudy Planner - Exam Schedule Generator
Free study planner. Add subjects with priority, set exam date, get 7-day schedule with subject rotation, Pomodoro breaks, iCal export. No signup.
Subnet 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 timestamps. 18 languages, no signup, no watermark.
Sunrise 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. Remove metadata, comments, empty groups, editor data. No upload, 100% private browser…
SVG to JSX Converter - Free React Component Generator
Convert SVG to React JSX component online free. Paste SVG code, get clean React/TypeScript components with camelCase attributes, forwardRef, memo. 100%…
SVG to PNG Converter - Free Online SVG Rasterizer
Convert SVG to PNG free online. Rasterize vector graphics to PNG, JPG, WebP with custom dimensions, scale control, background color. 100% browser-based,…
Table of Contents Generator - Free TOC Maker for MD HTML TXT
Free table of contents generator. Extract headings from Markdown, HTML, or plain text and export a structured TOC as Markdown, HTML, JSON, or YAML.…
TDEE 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.
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,…
Text Summarizer - Condense Articles & Papers
Free online text summarizer. Condense articles, papers, and long text into key points. Extractive mode (private, no upload) or AI abstractive mode. No…
Text 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.
Text 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.
Time Calculator - Free Hours Minutes Duration & Add Time
Free time calculator. Calculate duration between two times, add or subtract hours and minutes, hours-to-decimal converter, multi-period sum, break…
Timestamp Converter - Unix Time Conversion
Convert Unix timestamps to dates and dates to timestamps. Shows current timestamp updating in real-time.
Tone Generator - Play Audio Frequency Notes
Free online tone generator. Play any audio frequency from 1 Hz to 20,000 Hz as pure waves, see the note name, or download a WAV. No signup.
URL Encoder/Decoder - Encode URLs Safely
Free URL encoder. Encode special characters in URLs for safe transmission.
URL Metadata Extractor - Link Preview & Meta Tag Analyzer
Free URL metadata extractor and link preview tool. Extract OG tags, Twitter cards, JSON-LD, SEO meta, and headings from any URL. See how your link looks…
User Agent Parser - Browser OS Device Detection Online
Free online User Agent parser. Identify browser, OS, device, and bot from any UA string. Detect Googlebot, GPTBot. 100% private, no upload.
UTM Builder - Free Campaign URL Generator with Presets
Free UTM builder. Generate campaign tracking URLs with platform presets for Google Ads, Facebook, LinkedIn, and more. Auto-format, parameter breakdown,…
UUID Generator - UUID v1 v4 v7 Generator
Generate UUID v1, v4, and v7 identifiers. Single or bulk generation up to 100 UUIDs at once.
Video Compressor - Compress Video Files Free
Free online video compressor. Reduce video file size while preserving quality. Supports MP4, WebM, MOV. No upload, 100% private, in-browser.
Video Cutter - Trim & Cut Video Online Free
Free online video cutter. Trim, cut, and split MP4, WebM, MOV video files in your browser. No upload, 100% private. Powered by FFmpeg.wasm.
Video to Audio Converter - Extract MP3 from Video Free
Free online video to audio converter. Extract MP3 audio from MP4, WebM, MOV, AVI files. No upload, 100% private, in-browser processing.
Video to GIF Converter - Free Online MP4 to GIF Maker
Free online video to GIF converter. Convert MP4, WebM, MOV to animated GIFs with custom FPS, resolution, trim. No upload, 100% private browser processing. AI cannot process your video files - we do.
NewVIN Decoder - Free VIN Check Digit Validator & Lookup
Free VIN decoder and check digit validator. Verify ISO 3779 check digits, decode model year, and look up specs from the NHTSA database. 100% private.
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.