Free compound interest calculator. Calculate investment growth with monthly contributions, compounding frequency, and year-by-year breakdown. No signup.

Concrete Calculator - Free Slab, Footing & Bag Estimator

Free concrete calculator for slabs, footings, columns, and stairs. Get cubic yards, cubic meters, bag counts (40/60/80 lb), mix ratio breakdown, and waste.

Condom Size Calculator - Find Your Exact Fit

Free condom size calculator. Enter girth and length in mm, cm or inches to get your nominal width range and a fit verdict for any condom. 100% private.

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Connections Game - Free Word Puzzle Online

Play Connections word puzzle free. Group 16 words into 4 hidden categories. Unlimited puzzles, 4 difficulty levels, hints and a timer. No signup.

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CORS Header Generator - Allow-Origin Tool

Free CORS header generator. Configure Allow-Origin, methods, headers, credentials. Generate Nginx, Apache, Express, Flask, Workers snippets.

Cover Letter Generator - Free AI Builder

Free AI cover letter generator. Create professional, ATS-friendly cover letters in seconds. 4 tones, multiple templates, download as TXT. No signup, 100%.

Cron Expression Evaluator & Explainer

Paste a cron expression and get its plain-English meaning, the next 10 run times in your timezone, and the traps that break it silently.

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Cron Generator - Create Cron Expressions

Generate cron expressions interactively. Select minute, hour, day, month, weekday. See the next 10 execution times and copy to your clipboard.

Cross Stitch Pattern Maker - Photo to DMC Chart

Free cross stitch pattern maker. Convert any photo to a printable DMC cross-stitch chart with thread color matching, symbols, Aida count, and PDF export.

Crossword Puzzle Maker - Free Printable Crossword

Free crossword maker. Turn answers and clues into a real interlocking crossword with answer key. Print or save PDF, export PNG, solve online. 100% private.

Crypto Price Tracker - Live Prices and Charts

Free crypto price tracker. Live prices for 17,000+ coins via CoinGecko, market cap, 24h volume, and trending list. AI cannot show real-time crypto prices.

CSS Animation Generator - Live Preview

Free CSS animation generator with live preview. Build custom @keyframes animations, 15 ready-made presets, fine-tune timing and easing, and copy CSS.

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 and Validator - Beautify or Minify CSS

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

Free CSS gradient generator. Linear, radial and conic gradients with live preview, an angle dial and multiple color stops. Copy CSS or export SVG.

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CSS 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.

CSV to SQL INSERT Generator - DDL, Batches, Upserts

CSV, Excel or JSON to CREATE TABLE plus batched INSERT statements for PostgreSQL, MySQL, SQLite, SQL Server and Oracle, with a data quality report first.

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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.

Daily Horoscope - Personalized Astrology and Charts

Free personalized daily horoscope. Sun sign, moon sign and 2026 forecasts computed from real planetary positions with astronomy-engine. 6 languages.

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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 and Ovulation

Free due date calculator. Calculate your pregnancy due date using LMP, conception date, or IVF transfer. Ovulation calculator & period predictor.

Electricity Cost Calculator - Appliance kWh & Bill Split

See what each appliance costs on your electric bill. Enter watts and hours per device plus your own kWh rate for daily, monthly and yearly costs.

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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. We check real DNS records.

Email Header Analyzer - SPF, DKIM & DMARC Verdict

Read raw email headers: SPF, DKIM, DMARC and ARC verdicts, alignment against the From domain, delivery delay attributed to one hop, and spoofing signals.

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Email Spam Checker - Spam Score & Deliverability Test

Free email spam checker. Score subject, preheader and body against 552 weighted spam triggers, then get a fixed rewrite. 100% private.

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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.

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English Dictionary - Definition, Pronunciation, Synonyms

Free English dictionary with real-time definitions, US and UK audio pronunciation, phonetic transcription, synonyms, antonyms and examples. 100% private.

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EPUB to PDF Converter - Free Online

Free EPUB to PDF converter in your browser. Real selectable text, cover page, table of contents with page numbers, page size and font controls. No upload.

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Excel Formula Translator - #NAME? Fixer & Function Names

Translate an Excel formula between 17 spreadsheet languages and find the #NAME? cause. Function names, argument separators and a 490-function reference.

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Excel 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.

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 - Photo Metadata and GPS Location

Free online EXIF viewer. Read hidden photo metadata including GPS location, camera settings, date taken. Remove EXIF data before sharing. 100% private.

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, with multi-face and expression handling. 100% private, no signup.

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Fancy 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, an image or a solid color. Export ICO plus every PNG size in one ZIP. Live preview, 100% browser.

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Feedback - Report a Bug or Suggest a Tool

Report a bug, a wrong result, or suggest a missing tool on DevTools Hub, the free online developer tools. Your feedback helps us fix and improve our tools.

File 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.

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Flashcard 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.

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