Everything runs on your machine.
100+ free tools for developers, marketers, students and everyday tasks — every byte is processed locally in your browser.
Utilities
07List Utilities
Union, intersection, flatten, dedupe, sort and filter lists — line by line.
String Utilities
Match, transform, run regex and analyse strings in a single pass.
Case Converter
Switch between camelCase, snake_case, PascalCase, kebab-case and more.
Regex Tester
Test regular expressions with live match highlighting and capture groups.
Cron Expression Explainer
Translate a cron expression into plain English and preview upcoming run times.
CIDR / Subnet Calculator
Compute network, broadcast, netmask and host range from an IPv4 CIDR block.
Chmod Calculator
Convert Unix file permissions between symbolic (rwx) and octal notation.
Converters
16CSV to JSON
Turn CSV data into clean JSON arrays with automatic type inference.
JSON to CSV
Flatten nested JSON arrays into spreadsheet-ready CSV.
Text to CSV
Reshape raw text into CSV with any delimiter — comma, tab, newline.
JSON Object to CSV
Map key–value objects and data pairs straight to CSV rows.
JSON Pivot
Pivot and transpose JSON arrays around the key fields you pick.
SQL to CSV
Export SQL result sets to CSV or rebuild INSERT statements.
Data Picker
Pull specific fields and columns out of CSV, JSON, TSV and YAML.
Unit Converter
Convert length, mass, temperature, data, speed, area and more.
Number Base Converter
Convert between binary, octal, decimal, hexadecimal and any base.
Time Zone Converter
Convert a date and time across world time zones.
JSON to TypeScript
Generate TypeScript interfaces from a sample JSON object.
.env to JSON
Convert between .env files and JSON in both directions.
Roman Numeral Converter
Convert between numbers and Roman numerals.
Number to Words
Spell out numbers as English words, including currency style.
Query String to JSON
Convert URL query strings to JSON and back.
JSON to Go Struct
Generate Go structs with json tags from a JSON sample.
Formatters
03Code Formatter
Format, minify and prettify code with live syntax highlighting.
JSON Formatter
Validate, beautify and minify JSON — including loose JS objects.
SQL Formatter
Format and beautify SQL queries with consistent keyword casing and indentation.
Generators
11Random Data
Spin up random strings, words, names, emails, numbers and JSON.
Hash Generator
Compute SHA-256, SHA-512, MD5 and more, entirely on-device.
UUID Generator
Mint RFC-4122 UUID v4 identifiers on demand.
Timestamp Converter
Translate Unix timestamps to human-readable dates and back.
File Generators
Produce sample CSV, JSON, XML, HTML, markdown and image files.
Password Generator
Generate strong random passwords and passphrases on-device.
QR Code Generator
Create QR codes for text, URLs and Wi-Fi — rendered in your browser.
Lorem Ipsum Generator
Generate placeholder lorem ipsum paragraphs, sentences and words.
Markdown Table Generator
Build Markdown tables from rows, or convert CSV into a Markdown table.
ULID & UUIDv7 Generator
Generate time-sortable ULID and UUID v7 identifiers in bulk.
.gitignore Generator
Build a .gitignore from common language and tool templates.
Data Tools
08Base64 Encode / Decode
Encode and decode Base64 strings with built-in validation.
URL Encode / Decode
Percent-encode URLs and untangle query parameters.
JWT / JWS Token Tool
Decode, verify and sign JWT / JWS with HS256, HS384 and HS512.
File Viewer & Previewer
Preview Markdown, HTML, JSON, XML, CSV and YAML in real time.
Encryption & Decryption
AES, PGP/RSA, HMAC, SHA, ROT13 and Caesar — all client-side.
Base58 & Base32 Encoder
Encode and decode text with Base58 and Base32.
JSON Diff
Compare two JSON documents and see what was added, removed or changed.
URL Parser
Break a URL into protocol, host, path, query parameters and hash.
Image Tools
05Image Compressor
Shrink JPG, PNG and WebP images in your browser — no upload, no quality sent anywhere.
Image Converter
Convert images between PNG, JPG and WebP locally on your device.
Image Resizer
Resize and crop images in your browser, with no upload.
Image to Base64
Turn an image into a Base64 data-URI for inline embedding.
Favicon Generator
Generate favicon PNGs and a multi-size .ico from any image.
PDF Tools
05Merge PDF
Combine multiple PDF files into one — entirely in your browser.
Split PDF
Split a PDF or extract page ranges, locally on your device.
Organize PDF
Reorder, rotate and delete PDF pages in your browser.
Images to PDF
Combine JPG and PNG images into a single PDF document.
PDF to Images
Render PDF pages to PNG images, all on your device.
Text Tools
04Word & Character Counter
Count words, characters, sentences, paragraphs and reading time as you type.
Slug Generator
Turn any text or title into a clean, URL-safe slug.
Text Diff Checker
Compare two blocks of text and highlight added and removed lines.
Morse Code Translator
Translate text to and from Morse code, with optional audio dots and dashes.
Web & CSS
06HEX, RGB & HSL Converter
Convert colors between HEX, RGB and HSL with a live swatch.
Color Contrast Checker
Check the WCAG contrast ratio between text and background colors.
CSS Gradient Generator
Design linear and radial CSS gradients with a live preview and copyable code.
HTML Entity Encoder / Decoder
Encode and decode HTML entities and numeric character references.
CSS Box Shadow Generator
Design CSS box-shadows with a live preview and copyable code.
CSS Border Radius Generator
Craft CSS border-radius with per-corner control and a live preview.
Business & Finance
09Loan & EMI Calculator
Calculate monthly payments, total interest and a full amortization schedule.
Compound Interest Calculator
Project savings growth with compounding and regular contributions.
Percentage Calculator
Work out percentages, percentage change and ratios.
Profit Margin & Markup Calculator
Compute profit margin, markup, profit and selling price.
Sales Tax & VAT Calculator
Add or extract sales tax / VAT from any amount.
Discount Calculator
Find the sale price and amount saved for any discount.
Break-even Calculator
Find the units and revenue needed to cover your costs.
ROI & CAGR Calculator
Measure return on investment and compound annual growth rate.
Tip & Bill Split Calculator
Split a bill and calculate the tip per person.
Education
08GPA Calculator
Calculate your weighted GPA from course grades and credit hours.
Grade Calculator
Work out your weighted course grade and the score you need on the final.
Statistics Calculator
Find mean, median, mode, range, variance and standard deviation of a data set.
Fraction Calculator
Add, subtract, multiply and divide fractions, with simplified results.
Quadratic Equation Solver
Solve ax² + bx + c = 0 with real or complex roots and the discriminant.
Citation Generator
Build APA, MLA and Chicago citations for books and websites.
Readability Score
Measure Flesch reading ease and grade level for your text.
Random Name Picker
Shuffle a list and pick random names or winners.
Health & Fitness
04BMI Calculator
Calculate Body Mass Index in metric or imperial units, with category.
Calorie & TDEE Calculator
Estimate BMR and daily calorie needs with the Mifflin-St Jeor formula.
Running Pace Calculator
Convert between pace, distance and time for your runs.
Water Intake Calculator
Estimate how much water to drink per day from your body weight.
Everyday
04Age Calculator
Find your exact age in years, months and days from a date of birth.
Date Difference Calculator
Count the days, weeks, months and years between two dates.
Date Add / Subtract
Add or subtract days, weeks or months from a date.
Random Number Generator
Generate random numbers in a range, with optional uniqueness.
Marketing & SEO
16Meta Tag Generator
Generate SEO meta tags — title, description, robots, canonical and social cards.
Open Graph Generator
Build Open Graph and card tags for rich link previews on social platforms.
UTM Campaign Builder
Build trackable campaign URLs with UTM parameters.
SERP Snippet Preview
Preview how your title and description appear in search results, with length limits.
Keyword Density Analyzer
Analyze keyword frequency and density in your content.
Robots.txt Generator
Create a robots.txt with allow / disallow rules and a sitemap reference.
XML Sitemap Generator
Turn a list of URLs into a valid XML sitemap.
Hashtag Generator
Turn keywords into clean, deduplicated hashtags.
Social Character Counter
Count characters against common post, caption and bio length limits.
CTR Calculator
Calculate click-through rate from clicks and impressions.
Conversion Rate Calculator
Work out conversion rate from conversions and visits.
CPM, CPC & CPA Calculator
Calculate CPM, CPC and CPA from spend, impressions, clicks and conversions.
ROAS Calculator
Measure return on ad spend from revenue and cost.
Engagement Rate Calculator
Compute engagement rate from interactions and audience size.
A/B Test Significance Calculator
Check whether an A/B test conversion result is statistically significant.
Email Signature Generator
Create a clean HTML email signature you can copy into your mail client.