100+ Free Online Tools for Developers, SEO & Everyone
Browser-based utilities across 10 categories — JSON, Base64, PDF, image, video, SEO, calculators and more. No signup, no upload, 100% private.
Developer Tools
JSON Formatter & Validator
Format, beautify, and validate JSON instantly. Errors with line numbers, runs 100% in your browser.
Base64 Encoder & Decoder
Encode or decode Base64 instantly with full UTF-8 and emoji support. No upload, runs in your browser.
UUID Generator (v4)
Generate random UUID v4 identifiers in bulk. RFC 4122 compliant, client-side, no signup.
Hash Generator
Compute MD5, SHA-1, SHA-256, and SHA-512 hashes from any text — all at once, in your browser.
URL Encoder & Decoder
Encode or decode URLs with percent-encoding. Choose encodeURI or encodeURIComponent. UTF-8 safe.
Regex Tester
Test and debug JavaScript regex with real-time match highlighting and capture-group colors.
Diff Checker
Compare two texts or code blocks side-by-side. Word-level highlighting, no signup, client-side.
Code Beautifier
Format and beautify HTML, CSS, and JavaScript. Expand minified files, fix indentation, copy in one click.
Cron Generator
Build cron expressions visually with plain-English descriptions and next-run preview. Supports cron, Quartz, AWS.
chmod Calculator
Set Linux file permissions visually. Numeric (755), symbolic (rwxr-xr-x), and ready-to-copy chmod command.
CSV to JSON
Convert CSV to JSON with header detection, custom delimiters, and quoted-field handling. Local-only.
JSON to CSV
Convert JSON arrays to CSV. Flattens nested objects with dot-notation columns. Excel-ready.
YAML to JSON
Convert YAML to JSON with full Kubernetes and Docker Compose support. Multi-document streams handled.
JSON to YAML
Convert JSON to clean YAML output. Anchor-friendly, Kubernetes-ready, customizable indentation.
XML to JSON
Convert XML to JSON keeping attributes and namespaces. Handles SOAP envelopes and large files.
JSON to XML
Convert JSON to XML with custom root element, attribute prefix, and pretty-print indentation.
Markdown to HTML
Convert Markdown to clean HTML with live preview. GFM tables, task lists, and code blocks supported.
JWT Decoder
Decode JWT tokens instantly. View header, payload, claims & expiration. 100% client-side.
SEO Tools
Word Counter
Count words, characters, sentences, paragraphs, plus reading time and platform character limits.
Character Counter
Count characters with and without spaces. Live limits for Twitter/X, Instagram, LinkedIn, and meta descriptions.
Meta Tag Generator
Generate SEO, Open Graph, and Twitter Card meta tags with live Google/Facebook/X preview.
Robots.txt Generator
Generate, validate & block AI bots with robots.txt.
Sitemap Generator
Build a valid XML sitemap with per-URL priority, changefreq, and lastmod. No crawl limit.
Lorem Ipsum Generator
Generate lorem ipsum placeholder text — words, sentences, paragraphs, or HTML-wrapped output.
Slug Generator
Convert any text or title into a clean, SEO-friendly URL slug. Transliteration for non-Latin scripts.
Open Graph Preview
Preview how your links appear on Facebook, X, LinkedIn, Discord, Slack & WhatsApp before publishing.
Marketing Tools
UTM Builder
Build UTM-tagged campaign URLs with all 5 parameters. Naming-convention validation and one-click copy.
QR Code Generator
Generate static QR codes with custom colors, logo, and SVG/PNG export. Static — no link tracking.
Hashtag Generator
Generate relevant hashtags for Instagram, TikTok, YouTube, and X from a keyword or topic.
Email Signature Generator
Build a professional HTML email signature with logo and social icons. Works in Gmail, Outlook, Apple Mail.
Privacy Policy Generator
Generate a privacy policy with GDPR, CCPA, and COPPA clauses. Website, app, or e-commerce templates.
Terms of Service Generator
Generate Terms of Service tailored to your site or app. Liability limits, governing law, dispute clauses.
Favicon Generator
Generate favicons from image, text, or emoji. ICO + PNG + Apple Touch Icon + webmanifest in one zip.
Productivity Tools
Pomodoro Timer
Focus timer with customizable work/break intervals, audio cues, and session count. No signup, no ads.
Password Generator
Generate strong random passwords or word passphrases instantly with a live entropy meter.
Timezone Converter
Convert and compare times across world cities. Drag-slider planner with DST and working-hours overlay.
Unix Timestamp Converter
Convert Unix epoch ↔ readable date. Seconds, milliseconds, relative time, and code snippets for 10+ languages.
Color Picker
Pick colors, generate harmonious palettes, check WCAG contrast, and convert HEX/RGB/HSL/OKLCH.
Image to Base64
Convert PNG, JPG, GIF, SVG, WebP to a Base64 data URI for inline HTML/CSS embedding. No upload.
Text Case Converter
Convert text between UPPER, lower, Title, Sentence, camelCase, PascalCase, snake_case, kebab-case.
Text Tools
Fancy Text Generator
Convert plain text into 30+ Unicode font styles — bold, cursive, monospace, fraktur. One-click copy.
Text to Speech
Read text aloud in 30+ languages using your browser's built-in voices. Adjustable speed, no signup.
Number to Words
Convert any number — including currency and decimals — to English words. Perfect for checks and legal docs.
Roman Numeral Converter
Convert numbers and dates to Roman numerals. Tattoo preview font, supports 1–3,999,999.
Text to Binary
Translate text ↔ binary, plus hex, octal, decimal. UTF-8 safe — handles emojis and CJK correctly.
Invisible Character
Copy invisible/blank Unicode characters — Hangul Filler, zero-width space, Braille blank, more.
Remove Line Breaks
Remove line breaks and extra whitespace. Optionally preserve paragraph breaks. Great for PDF/email cleanup.
Text Repeater
Repeat any text up to 10,000 times with custom separators (newline, comma, space, custom).
Image Tools
Image Compressor
Compress JPG, PNG, WebP, AVIF up to 80% smaller. Bulk, browser-only — files never upload.
Image Resizer
Resize images to exact pixels or social-media presets (Instagram, X, YouTube). Bulk supported.
Image Format Converter
Convert between PNG, JPG, WebP, AVIF, HEIC, BMP, GIF, SVG — bulk supported, runs in your browser.
HEIC to JPG Converter
Convert iPhone HEIC/HEIF photos to JPG or PNG. Batch up to 200 files, browser-only — no upload.
Background Remover
Remove image backgrounds with an in-browser AI model. Transparent PNG output, no upload to servers.
Image Cropper
Crop images with 1:1, 4:3, 16:9, 9:16, and custom aspect ratios. Drag handles, in-browser.
Rotate & Flip Image
Rotate images by any angle (90°, 180°, custom) or flip horizontally/vertically. Browser-only.
Add Watermark
Add text watermarks to images — opacity, tiled pattern, position, font & color. No upload.
Bulk Image Rename
Rename hundreds of images with custom patterns, numbering, padding, prefix/suffix. Browser-only.
PDF Tools
Merge PDF
Combine multiple PDFs into one, reorder pages by drag-and-drop. Browser-only, no upload, no size limit.
Split PDF
Split PDF by page ranges, every N pages, or one page per file. Browser-only — no upload.
PDF to Image
Convert PDF pages to JPG, PNG, or WebP at adjustable DPI (72–600). Per-page selection, in-browser.
Image to PDF
Combine JPG, PNG, WebP, HEIC images into a single PDF. Page size, orientation, margin controls.
Compress PDF
Compress PDFs by re-encoding embedded images. Light/medium/heavy presets, in-browser, no upload.
PDF to Word
Convert PDF to editable Word (DOCX) keeping text layout. Browser-only — files stay local.
Word to PDF
Convert DOCX to PDF preserving fonts and layout. Browser-only — your document never uploads.
PDF Password Protect
Encrypt PDFs with a user or owner password and AES encryption. Browser-only — no upload.
Unlock PDF
Remove the password and copy/print restrictions from PDFs you own. Browser-only, no upload.
Rotate PDF
Rotate individual PDF pages or all pages by 90°/180°/270°. Save permanently, browser-only.
PDF Editor & Annotator
Add text, highlights, freehand drawing, shapes, and signatures to PDFs. Browser-only — no upload.
Calculators
Personal Loan Calculator
Calculate personal loan payments, interest, and credit score impacts.
Age Calculator
Calculate exact age in years, months, days, hours, minutes. Birthday countdown and age-difference mode.
Percentage Calculator
Find X% of Y, percentage change, increase, decrease, and reverse percentage — with formulas shown.
Random Number Generator
Generate cryptographically secure random numbers, roll dice, flip coins.
BMI Calculator
Calculate BMI in metric (kg/cm) or imperial (lb/ft). Visual category scale, healthy range by age.
Tip Calculator
Calculate tips and split bills instantly. Choose tip percentage, divide among friends, see per-person totals with round up option.
Salary Calculator
Convert salary between hourly, weekly, biweekly, monthly & annual. Estimate take-home pay after taxes.
GPA Calculator
Calculate semester and cumulative GPA on a 4.0 scale.
Discount Calculator
Calculate sale prices, savings, and double discounts instantly.
Date Calculator
Calculate days between dates or add/subtract days from any date.
Compound Interest Calculator
Project savings growth with daily, monthly, or yearly compounding and recurring contributions. Visual chart.
Loan Calculator
Calculate monthly payments, see full amortization, and model extra payments. Export CSV / PDF / Excel.
Debt Payoff Calculator
Compare Snowball vs. Avalanche strategies to find the fastest, cheapest way to pay off your debts.
Mortgage Calculator
Calculate monthly mortgage payments with principal, interest, taxes, PMI, insurance & HOA. Free amortization schedule and loan comparison.
ROI Calculator
Calculate return on investment instantly. Compare investments, see annualized returns, analyze marketing ROI.
Profit Margin Calculator
Calculate profit margin, markup %, and net profit instantly. Convert margin to markup, find break-even revenue.
VAT Calculator
Add or remove VAT from any price. Pre-loaded rates for 40+ countries including UK, EU. Reverse VAT calculation.
Home Affordability Calculator
Calculate how much home you can afford based on income, debts, and the 28/36 rule. See monthly payment breakdown with taxes, insurance, and PMI.
Mortgage Refinance Calculator
Compare current vs. new mortgage, calculate break-even point, monthly savings, and lifetime cost impact of refinancing.
Auto Loan Calculator
Calculate your car payment with credit score-based rates, trade-in, down payment, and sales tax. New and used car support.
Retirement Savings Calculator
Project your retirement savings with compound growth, Social Security, inflation adjustment, and the 4% safe withdrawal rule.
Rent vs. Buy Calculator
Compare the true cost of renting vs. buying a home over time, including equity, taxes, PMI, maintenance, and investment opportunity cost.
Savings Goal Calculator
Find exactly how much to save daily, weekly, or monthly to reach any financial goal with compound interest and inflation adjustment.
Mortgage Payoff Calculator
See how much interest you save and years you cut by paying extra on your mortgage. Compare strategies: extra monthly, bi-weekly, or lump sum.