All 373 Free Online Developer Tools

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Free Sudoku - Daily Challenge & 4 Difficulty Levels

Free online Sudoku. 4 difficulty levels, daily challenge, hints with logic explanation, pencil notes and statistics. 100% private, no signup, no ads.

Popular

Free Tarot Card Reading Online - Celtic Cross, Yes/No, Daily

Free tarot card reading online. 78 authentic Rider-Waite cards, 7 spreads (Daily, Yes/No, Past-Present-Future, Celtic Cross, Birth Card, Love, Career).

Free Text Diff Checker - Compare Text & Code Online

Free online text diff checker to compare text and code. Side-by-side view with syntax highlighting. Compare JSON, XML, code files and find differences.

Free Tile Calculator - Floor, Wall & Pattern Estimator

Free tile calculator with multi-room aggregation, 5 patterns, box optimization, grout and thinset estimator, waste factor. 100% private.

Free Time Zone Converter - World Clock

Free time zone converter. Convert time between cities instantly. See current time in multiple locations. No signup required.

Free Tip Calculator - Quick & Easy Restaurant Tip Tool

Free tip calculator for restaurants. Calculate tip amount, split bills, and see per-person cost. Works offline, no signup required. Instant results.

Free Typing Test - WPM, Accuracy & Code Mode

Free online typing test with WPM, accuracy and code snippet modes (JavaScript, Python, SQL, HTML). Practice words, quotes, numbers and syntax. No signup.

Popular

Free URL Shortener - Shorten Long Links Instantly

Free URL shortener. Shorten long links instantly with no signup. Create clean, shareable short URLs for social media, messaging, and more.

Free Venn Diagram Maker - 2, 3, 4 Circles Online

Create 2, 3 or 4 circle Venn and Euler diagrams in your browser. Custom labels, colors, area-proportional sizing, SVG and PNG export. No signup.

Popular

Free YAML Validator - Validate & Format YAML Online

Free YAML validator and formatter. Validate YAML syntax, fix errors with line numbers, and format YAML for better readability. No signup required.

Gamepad Tester - Test Controller and Stick Drift

Free online gamepad tester. Test every button, trigger and analog stick. Measure stick drift and deadzone. Export a diagnostic report. 100% private.

GIF Maker - Video & Images to GIF Free

Free GIF maker. Create animated GIFs from video or images. Trim, resize, FPS, loop, reverse. 100% private, no upload, no signup.

GIF to MP4 Converter - Free Online GIF to Video

Free GIF to MP4 converter. Convert animated GIFs to MP4 video files online. Reduce GIF file size by 90% with H.264 compression. 100% private, no upload.

Gold Price Tracker - Live Spot Gold Prices & Charts

Track live gold spot prices (XAU/USD). Free real-time gold price tracker with interactive charts. Updated every minute. No signup required.

GPA Calculator - 4 Scales, Semester, Cumulative & Target

Free GPA calculator with 4 scales, unlimited semesters, prior GPA integration, a target GPA planner, and Honors, AP and IB classes.

Grade Calculator - Weighted Average & Final Exam

Free grade calculator. Calculate weighted average grade, what you need on the final exam, and GPA. No signup, 100% private browser tool.

Graphing Calculator - Roots, Area & Fit

Free graphing calculator. Plot functions, polar, parametric and implicit curves, then get roots, turning points, area between curves, integrals and R2.

Habit Tracker - Free Daily Streak Builder

Free online habit tracker. Daily routines, streaks, heatmap, goals. No signup, 100% private. AI cannot track your habits - we do.

Hash Generator - MD5 SHA-1 SHA-256 SHA-512

Generate MD5, SHA-1, SHA-256 and SHA-512 hashes for any text or file, and compare two hashes to verify a download. Runs locally, nothing is uploaded.

Hashtag Generator - Instagram, TikTok, YouTube, Twitter

Free hashtag generator for Instagram, TikTok, YouTube, Twitter, LinkedIn and Facebook. Platform-aware rules, 6 categories, copy-all, live character count.

Heart Rate Zone Calculator - 5 Zones by Age

Free heart rate zone calculator. Enter your age to get all five training zones in bpm, compare four max HR formulas, and find your personal Zone 2 range.

HEIC to JPG Converter - Free iPhone Photo Converter

Free online HEIC to JPG converter. Convert iPhone HEIC photos to JPEG instantly in your browser. Batch convert unlimited photos. No upload, 100% private.

htaccess Redirect Tester - Test Rewrite Rules Online

Free htaccess redirect tester. Paste .htaccess rules and a URL, see which rule matched and why, and get the corrected line for the mistake.

HTML Entity Encoder/Decoder - Encode Special Characters

Free online HTML entity encoder and decoder. Encode special characters like &, <, > and quotes to HTML entities, and decode them back. 100%.

HTML Formatter - Format & Beautify HTML

Free HTML formatter. Beautify and minify HTML with correct indentation, and catch unclosed tags and invalid nesting before production. No upload.

HTML Playground - Live Code Editor Preview

Free HTML playground with live preview. Write and test HTML, CSS, JavaScript code instantly in your browser. No signup, 100% private.

HTML Table Generator - Visual Table Builder

Free HTML table generator. Create responsive HTML tables visually with editable cells, border styling, striped rows, and live preview. Copy clean HTML.

HTML to Image Converter - Free HTML to PNG, JPG, WebP

Free HTML to image converter. Paste HTML or CSS, render to PNG, JPG, or WebP with custom width, height, scale, and background. Full-page or viewport-only.

HTML to Markdown Converter - Free Online Tool

Free HTML to Markdown converter. Paste HTML, get clean Markdown. Supports tables, code blocks, links, images, nested lists, heading styles, and more. 100%.

HTML to PDF Converter - Free Online HTML to PDF

Free HTML to PDF converter. Paste HTML code, customize page size, orientation and margins. Live preview, download as PDF. No upload, 100% private browser.

HTTP Status & Header Checker Online

Free HTTP status checker. Check response codes, security headers, redirect chain, and response time for any URL. AI cannot check real HTTP headers - we do.

IBAN Validator and Checker - Validate Numbers

Free IBAN validator and checker. Validate International Bank Account Numbers with MOD-97 checksum. Supports 80+ countries. 100% private browser. No signup.

Image Color Picker - Pick Colors from Photo Online

Free online image color picker. Upload any photo and click to pick exact pixel colors. Get HEX, RGB, HSL, CMYK values instantly. No upload, 100% private.

Image 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.

Popular

Image Cropper - Crop Photos with Aspect Ratio

Free online image cropper. Crop with aspect ratio presets, rotate, flip and zoom. Social media sizes for Instagram, Facebook and Twitter. No upload.

Popular

Image Enhancer - Free Photo Quality Booster

Free image enhancer. Brightness, contrast, saturation, vibrance, sharpness, denoise, HDR and color temp in real time. 9 pro filters plus Auto Enhance.

Popular

Image Extender - AI Outpaint & Uncrop Free Online

Free AI image extender. Outpaint & uncrop photos to 16:9, 9:16, 21:9, 1:1, social ratios with 5 fill algorithms. No signup, 100% private.

Image Format Converter - Free Online JPG PNG WebP Converter

Free online image format converter. Convert between JPG, PNG, WebP, GIF, BMP, TIFF instantly. No upload, 100% private, browser-based conversion.

Image to Base64 Converter - Encode Images Online Free

Free online image to base64 converter. Convert any image to base64 string, data URI, HTML img tag, or CSS url(). Supports PNG, JPG, WebP, GIF. 100%.

Image to Excel Converter - Free JPG PNG to XLSX Online

Free image to Excel converter. Convert JPG, PNG, WebP, HEIC photos, scanned tables and screenshots to editable XLSX. Auto-detect rows and columns.

Image to PDF - Convert JPG PNG WebP HEIC to PDF Free

Free image to PDF converter. Combine JPG, PNG, WebP, HEIC, BMP, GIF into one PDF. Page size, orientation, margins. No upload, 100% private.

Popular

Image to Word Converter - Free JPG PNG to DOCX Online

Free image to Word converter. Convert JPG, PNG, WebP, GIF, BMP, HEIC photos into editable DOCX, RTF, or TXT. 12+ languages, batch OCR, 100% private.

Image Upscaler - AI Enhance Photos to 4K

Upscale images to 2x, 3x or 4x with edge-aware sharpening and denoise controls so photos stay sharp. In your browser, no upload, no signup.

Image Vectorizer - Free PNG JPG to SVG Converter Online

Free image vectorizer. Convert PNG, JPG, WebP, BMP and GIF to scalable SVG in your browser. 9 presets plus color count, blur and threshold. No upload.

Popular

Image Watermark - Add Text and Logo to Photos

Free online image watermark tool. Add text or logo watermarks to protect your photos. Custom position, opacity, rotation, tile mode, font, color. 100%.

Income Tax Calculator 2026 - US India UK

Free income tax calculator 2026 with US federal, India new/old regime, and UK brackets. No signup, private. AI gives wrong tax brackets.

Inflation Calculator - CPI Dollar Adjuster

Adjust any dollar amount for real US inflation with official monthly CPI data since 1913. Shows exact indexes used. 100% private.

Investment Calculator - Profit and Portfolio Tracker

Free investment calculator with portfolio tracker. Calculate stock profit, ROI, dividend yield, and average cost basis across multiple lots. No signup.

IP Address Lookup - Find Your IP Address

Find your public IP address, then the ISP, country, city and connection type behind it. Paste any address to look it up too. No signup, lookups not stored.

Is It Down? - Website Down Checker

Free website down checker. Check if any website is down for everyone or just you. Real-time status, response time, and HTTP code. No signup, 100% free.

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