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.
NewBrowse by Category
11 categoriesView all 323 tools (alphabetical)
CSS Box Shadow Generator - Live Preview
Free CSS box shadow generator. Multi-layer shadows, depth presets, inset toggle, live preview. Copy production-ready CSS. No signup, 100% browser-based.
CSS Filter Generator - Visual CSS Filter Builder
Free CSS filter generator. Visually create CSS filter effects for images and elements. Blur, brightness, contrast, grayscale, sepia, hue-rotate and more.…
CSS Flexbox Generator - Visual Flex Layout Builder
Free CSS flexbox generator with interactive visual builder. Create responsive flex layouts with direction, wrap, justify, align, gap. Copy CSS code.
CSS 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 Layout Builder
Free CSS grid generator with drag-and-drop builder. Create responsive grid layouts, columns, rows, gaps. Copy production CSS.
CSS to Tailwind Converter - Free Online Tool
Free CSS to Tailwind converter. Convert CSS properties to Tailwind utility classes instantly. 100+ properties supported.
cURL to Code Converter - Python, Node, Go, PHP, C#
Convert curl commands to Python, Node, Go, PHP, or C# code. Deterministic parser, 100% in-browser, no upload, no signup, and free to use forever.
Date Calculator - Days Between Dates & Date Arithmetic
Free online date calculator. Calculate days between dates, add or subtract days/weeks/months/years from any date, and compute business days. 100% private…
Days 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.
Debt Payoff Calculator - Snowball & Avalanche Free
Free debt payoff calculator. Compare avalanche vs snowball, see your debt-free date, total interest, and month-by-month payoff plan. No signup.
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 AVMA + UCSD formulas. Breed presets, life stages, chart. No signup, private.
Domain Age Checker - Free WHOIS Domain Age Lookup
Free domain age checker. Check how old any domain is, creation date, expiry date, registrar, and nameservers. Instant WHOIS lookup, no signup required. AI…
Drawing Board - Free Online Whiteboard & Sketch Pad
Free online drawing board and whiteboard. Sketch, draw shapes, add text, and save as PNG. No signup, no upload, 100% private browser-based canvas tool. AI…
Due Date Calculator - Pregnancy Due Date & Ovulation…
Free due date calculator. Calculate your pregnancy due date using LMP, conception date, or IVF transfer. Ovulation calculator & period predictor…
Email Authentication Checker - SPF DKIM DMARC Check Online
Free email authentication checker. Check SPF, DKIM, and DMARC DNS records for any domain. Fix email deliverability. AI cannot check real DNS records - we…
Email 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.
Engagement Rate Calculator - Multi-Platform Social Media
Free engagement rate calculator. 6 platforms (IG/TikTok/YT/X/FB/LI), 3 formulas, 5 tier benchmarks, weighted engagement. No signup.
NewExcel to PDF Converter - Free Online XLSX to PDF
Free online Excel to PDF converter. Convert XLSX and XLS files to PDF directly in your browser. Preserves tables, multiple sheets, and formatting. No…
Excel Viewer - Free Online XLSX Viewer & Converter
Free online Excel viewer and converter. View XLSX, XLS, CSV files without Excel. Convert to JSON, CSV format. 100% private browser processing, no upload…
EXIF Viewer - Read Photo Metadata & Remove GPS Location Free
Free online EXIF viewer. Read hidden photo metadata including GPS location, camera settings, date taken. Remove EXIF data before sharing. 100% private, no…
Face Age Estimator - How Old Do I Look? Free AI Age Detector
Free AI face age estimator. Detect how old you look in any photo or via live camera. 100% private browser processing, no upload, no signup. Multi-face, expressions & gender. AI cannot analyze real faces - we do.
NewFancy Text Generator - Cool Unicode Fonts and Stylish Text
Free fancy text generator. Convert plain text into 30+ cool Unicode font styles. Bold, italic, script, gothic, circled. No signup, 100% private.
Favicon Generator - Free ICO, PNG Favicon Creator Online
Free favicon generator. Create favicons from text, emoji, image upload, or solid color. Export ICO + all PNG sizes in one ZIP. Live preview, 100% browser-based. AI cannot generate .ico binary files - we do.
NewFile Checksum Verifier - Verify MD5 SHA-1 SHA-256 SHA-512
Verify file checksums after downloading. Compute MD5, SHA-1, SHA-256, SHA-512 hashes from any file. 100% private browser processing, no upload.
File Opener - Open APK, RAR, DLL, DAT, BIN Online
Free online file opener. Detect, view, and extract 50+ file types (APK, RAR, ZIP, DLL, DAT, BIN, DOCX) using magic numbers. Browser-only, no upload, 100% private. AI cannot parse real binary files - we do.
NewFlashcard Maker - Free Spaced Repetition Study Cards
Free flashcard maker with spaced repetition. Create unlimited decks, paste CSV/tab lists, study with Again/Hard/Good/Easy grading, track accuracy and…
Fraction Calculator - Add, Subtract, Multiply & Divide
Free fraction calculator. Add, subtract, multiply, divide fractions. Simplify, convert mixed numbers, compare fractions. Step-by-step solutions. No…
Free 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 AI Detector - Check If Text Is AI Generated
Free AI content detector using multi-model voting (Groq, Gemini, NVIDIA). Detect ChatGPT, Claude, Gemini text with sentence highlighting. No signup.
NewFree AI Humanizer - Make AI Text Undetectable
Free AI humanizer with 5-stage DeAI pipeline. Bypass GPTZero, Turnitin, Copyleaks. No signup, no word limit, no paywall. Real MAGE, Burstiness, and brandonwise detector scores shown. Self-hosted.
NewFree AI Paraphrasing Tool - Rewrite Text Online
Free AI paraphrasing tool that rewrites text while preserving meaning. 8 modes including humanizer makes AI text sound natural. No signup, no limits.
Free AI Plagiarism Checker - AI-Powered Content Originality Test
Free AI plagiarism checker that searches the web for duplicate content. Get similarity percentage, source URLs, and suggestions. No signup required.
Free AI PPT Maker - Generate Editable PowerPoint Slides
Free AI PPT maker with 4 professional styles. Generates real editable .pptx files in 10 seconds. No signup, no watermark, no daily limit. Uses Groq Llama 3.3 70B + PptxGenJS. 10 languages. AI cannot generate valid .pptx binary.
NewFree AI Prompt Engineer - 8 Platforms 88 Templates Sandbox
Free AI prompt engineer. 88 ready-to-use prompts for ChatGPT, Claude, Midjourney, DALL-E, Stable Diffusion, Gemini, Llama, Copilot. Live test sandbox with…
Free AI Resume Builder - Professional Resume Generator
Free AI-powered resume builder. Enter your details and get a professionally formatted resume instantly. No signup required.
Free AI Sentence Rewriter - 8 Modes Side-by-Side
Free AI sentence rewriter. 8 modes (standard, fluency, formal, simple, creative, expand, shorten, humanize) with side-by-side sentence comparison and…
Free AI Translator - AI Multi-Language Translation
Free AI translator supporting 50+ languages. Translate text instantly with context-aware translations. No signup required.
Free ATS Resume Checker - Score & Scan Your Resume
Free AI-powered ATS resume checker. Score your resume 0-100 against any job description. Detects missing hard skills, soft skills, keywords, and ATS format issues. 5-priority Jobscan-style scoring, AI suggestions, 100% private. No signup, unlimited scans. 99% of Fortune 500 use ATS - this tool beats them.
NewFree Audio Converter - Convert MP3, WAV, FLAC, OGG, AAC
Free online audio converter. Convert between MP3, WAV, FLAC, OGG, M4A, AAC, OPUS, AIFF. Adjust bitrate, sample rate, channels. No upload, 100% private, in-browser FFmpeg.wasm.
NewFree Binary Hex Converter - Convert Binary to Decimal, HEX, ASCII
Free online binary hex converter. Convert between binary, decimal, hex, and ASCII text. Instant conversion, no upload needed. Developer tool for encoding.
Free BMI Calculator - Body Mass Index Checker
Free BMI calculator to check your body mass index. Supports metric and imperial units. Instant results with health category classification. No signup required.
Free Book Search & ISBN Lookup - 30M+ Open Library
Search 30+ million books by title, author, or ISBN-10/ISBN-13. Get covers, publisher, year, page count, subjects, and links to Open Library, Google Books, WorldCat, Amazon. AI cannot accurately recall book metadata - we use the live Open Library catalog. No signup, 100% private.
NewFree Case Converter - Convert Text Case Online
Free online case converter. Convert text to uppercase, lowercase, title case, sentence case, camelCase, snake_case, kebab-case, and more. Instant results.
Free Citation Generator - APA, MLA, Chicago
Free AI citation generator. Generate citations in APA, MLA, Chicago, Harvard, and IEEE formats. Just describe your source and get a formatted citation.
Free Color Palette Extractor - Extract Colors from Image
Free online color palette extractor. Extract dominant colors from any image as HEX, RGB, HSL values. Download CSS variables or JSON. No signup required.
Free Currency Converter - 166+ Currencies Exchange Rates
Free currency converter. Convert between 166+ world currencies instantly. Live exchange rates, swap currencies, search by country or currency code.
Free Daily Horoscope - Personalized Astrology & Birth Chart
Free personalized daily horoscope. AI cannot compute real planetary transits or natal charts - we use astronomy-engine for accurate sun sign, moon sign, 2026 forecasts. 6 languages, 100% private.
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.
NewFrequently 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.