Free online tools that run in your browser.

130+ tools for PDFs, images, text, code and everyday maths — designed to run on your device. No sign-up.

Utilities

List Utilities

Union, intersection, flatten, dedupe, sort and filter lists — line by line.

Utilities

String Utilities

Match, transform, run regex and analyse strings in a single pass.

Utilities

Case Converter

Switch between camelCase, snake_case, PascalCase, kebab-case and more.

Utilities

Regex Tester

Test regular expressions with live match highlighting and capture groups.

Utilities

Cron Expression Explainer

Translate a cron expression into plain English and preview upcoming run times.

Utilities

CIDR / Subnet Calculator

Compute network, broadcast, netmask and host range from an IPv4 CIDR block.

Utilities

Chmod Calculator

Convert Unix file permissions between symbolic (rwx) and octal notation.

Utilities

Cron to systemd Timer Converter

Turn a cron line into a systemd OnCalendar= value plus .timer and .service files. Runs in your browser.

Utilities

EML Viewer

Open .eml email files to read headers, text and HTML and save attachments. Remote images and trackers are blocked.

Converters

CSV to JSON

Turn CSV data into clean JSON arrays with automatic type inference.

Converters

JSON to CSV

Flatten nested JSON arrays into spreadsheet-ready CSV.

Converters

Text to CSV

Reshape raw text into CSV with any delimiter — comma, tab, newline.

Converters

JSON Object to CSV

Map key–value objects and data pairs straight to CSV rows.

Converters

JSON Pivot

Pivot and transpose JSON arrays around the key fields you pick.

Converters

SQL to CSV

Export SQL result sets to CSV or rebuild INSERT statements.

Converters

Data Picker

Pull specific fields and columns out of CSV, JSON, TSV and YAML.

Converters

Unit Converter

Convert length, mass, temperature, data, speed, area and more.

Converters

Number Base Converter

Convert between binary, octal, decimal, hexadecimal and any base.

Converters

Time Zone Converter

Convert a date and time across world time zones.

Converters

JSON to TypeScript

Generate TypeScript interfaces from a sample JSON object.

Converters

.env to JSON

Convert between .env files and JSON in both directions.

Converters

Roman Numeral Converter

Convert between numbers and Roman numerals.

Converters

Number to Words

Spell out whole numbers as English words.

Converters

Query String to JSON

Convert URL query strings to JSON and back.

Converters

JSON to Go Struct

Generate Go structs with json tags from a JSON sample.

Converters

Subtitle Sync Fixer

Fix out-of-sync subtitles: shift all cues, correct drift with two reference points, and convert between SRT and VTT.

Formatters

Code Formatter

Format and minify JSON, CSS, HTML and JavaScript.

Formatters

JSON Formatter

Validate, beautify and minify JSON — including loose JS objects.

Formatters

SQL Formatter

Format and beautify SQL queries with consistent keyword casing and indentation.

Generators

Random Data

Spin up random strings, words, names, emails, numbers and JSON.

Generators

Hash Generator

Compute SHA-256, SHA-512, MD5 and more, right in your browser.

Generators

UUID Generator

Mint RFC-4122 UUID v4 identifiers on demand.

Generators

Timestamp Converter

Translate Unix timestamps to human-readable dates and back.

Generators

File Generators

Produce sample CSV, JSON, XML, HTML, markdown and image files.

Generators

Password Generator

Generate strong random passwords and passphrases on-device.

Generators

QR Code Generator

Free QR code designer: custom shapes, colours, logo and frame. Wi-Fi, vCard, UPI and more. PNG, SVG or JPEG, no watermark.

Generators

Lorem Ipsum Generator

Generate placeholder lorem ipsum paragraphs, sentences and words.

Generators

Markdown Table Generator

Build Markdown tables from rows, or convert CSV into a Markdown table.

Generators

ULID & UUIDv7 Generator

Generate time-sortable ULID and UUID v7 identifiers in bulk.

Generators

.gitignore Generator

Build a .gitignore from common language and tool templates.

Data Tools

Base64 Encode / Decode

Encode and decode Base64 strings with built-in validation.

Data Tools

URL Encode / Decode

Percent-encode URLs and untangle query parameters.

Data Tools

JWT / JWS Token Tool

Decode, verify and sign JWT / JWS with HS256, HS384 and HS512.

Data Tools

File Viewer & Previewer

Preview Markdown, HTML, JSON, XML, CSV and YAML in real time.

Data Tools

Encryption & Decryption

AES, PGP/RSA, HMAC, SHA, ROT13 and Caesar — all client-side.

Data Tools

Base58 & Base32 Encoder

Encode and decode text with Base58 and Base32.

Data Tools

JSON Diff

Compare two JSON documents and see what was added, removed or changed.

Data Tools

URL Parser

Break a URL into protocol, host, path, query parameters and hash.

Data Tools

GPX Converter

Convert GPX, KML and GeoJSON tracks, or export to CSV, with distance and elevation stats. Runs in your browser.

Data Tools

VCF to CSV Converter

Convert vCard (.vcf) contacts to CSV for Excel, Google Contacts or Outlook — runs in your browser.

Data Tools

ICS File Viewer

Open an .ics calendar file as a table in your time zone and export it to CSV — runs in your browser.

Data Tools

HAR File Sanitizer

Remove cookies, tokens, API keys and JWTs from a HAR file before you share it with support. Processed on your device.

Image Tools

Image Compressor

Shrink JPG, PNG and WebP images right in your browser, with a quality slider.

Image Tools

Photo & Video Metadata Remover

See and remove GPS, camera, date and software metadata from JPEG, PNG, WebP, MP4 and MOV files, without re-encoding.

Image Tools

Image Converter

Convert images between PNG, JPG and WebP locally on your device.

Image Tools

Image Resizer

Resize and crop images right in your browser.

Image Tools

Image to Base64

Turn an image into a Base64 data-URI for inline embedding.

Image Tools

Favicon Generator

Generate favicon PNGs and a multi-size .ico from any image.

PDF Tools

Merge PDF

Combine multiple PDF files into one, right in your browser.

PDF Tools

Split PDF

Split a PDF or extract page ranges, locally on your device.

PDF Tools

Organize PDF

Reorder, rotate and delete PDF pages in your browser.

PDF Tools

Images to PDF

Combine JPG and PNG images into a single PDF document.

PDF Tools

PDF to Images

Render PDF pages to PNG images, all on your device.

Coming soon PDF Tools

PDF Metadata Remover

View, edit or remove PDF title, author, dates and XMP metadata. Processed on your device.

Text Tools

Word & Character Counter

Count words, characters, sentences, paragraphs and reading time as you type.

Text Tools

Slug Generator

Turn any text or title into a clean, URL-safe slug.

Text Tools

Text Diff Checker

Compare two blocks of text and highlight added and removed lines.

Text Tools

Morse Code Translator

Translate text to and from International Morse code — letters A–Z and digits 0–9.

Text Tools

Markdown to PDF

Write or paste Markdown, preview it live, and export to PDF or HTML — all in your browser.

Text Tools

Homoglyph Detector

Spot lookalike Unicode letters (Cyrillic а, Greek Η) and invisible characters in text. Runs in your browser.

Web & CSS

HEX, RGB & HSL Converter

Convert colors between HEX, RGB and HSL with a live swatch.

Web & CSS

Color Contrast Checker

Check the WCAG contrast ratio between text and background colors.

Web & CSS

CSS Gradient Generator

Design linear and radial CSS gradients with a live preview and copyable code.

Web & CSS

HTML Entity Encoder / Decoder

Encode and decode HTML entities and numeric character references.

Web & CSS

CSS Box Shadow Generator

Design CSS box-shadows with a live preview and copyable code.

Web & CSS

CSS Border Radius Generator

Craft CSS border-radius with per-corner control and a live preview.

Business & Finance

Loan & EMI Calculator

Calculate monthly payments, total interest and a full amortization schedule.

Business & Finance

Compound Interest Calculator

Project savings growth with compounding and regular contributions.

Business & Finance

Percentage Calculator

Work out percentages, percentage change and ratios.

Business & Finance

Profit Margin & Markup Calculator

Compute profit margin, markup, profit and selling price.

Business & Finance

Sales Tax & VAT Calculator

Add or extract sales tax / VAT from any amount.

Business & Finance

Discount Calculator

Find the sale price and amount saved for any discount.

Business & Finance

Break-even Calculator

Find the units and revenue needed to cover your costs.

Business & Finance

ROI & CAGR Calculator

Measure return on investment and compound annual growth rate.

Business & Finance

Tip & Bill Split Calculator

Split a bill and calculate the tip per person.

Education

GPA Calculator

Calculate your weighted GPA from course grades and credit hours.

Education

Grade Calculator

Work out your weighted course grade and the score you need on the final.

Education

Statistics Calculator

Find mean, median, mode, range, variance and standard deviation of a data set.

Education

Fraction Calculator

Add, subtract, multiply and divide fractions, with simplified results.

Education

Quadratic Equation Solver

Solve ax² + bx + c = 0 with real or complex roots and the discriminant.

Education

Citation Generator

Build APA, MLA and Chicago citations for books and websites.

Education

Readability Score

Measure Flesch reading ease and grade level for your text.

Education

Random Name Picker

Shuffle a list and pick random names or winners.

Health & Fitness

BMI Calculator

Calculate Body Mass Index in metric or imperial units, with category.

Health & Fitness

Calorie & TDEE Calculator

Estimate BMR and daily calorie needs with the Mifflin-St Jeor formula.

Health & Fitness

Running Pace Calculator

Convert between pace, distance and time for your runs.

Health & Fitness

Water Intake Calculator

Estimate how much water to drink per day from your body weight.

Everyday

Age Calculator

Find your exact age in years, months and days from a date of birth.

Everyday

Date Difference Calculator

Count the days, weeks, months and years between two dates.

Everyday

Date Add / Subtract

Add or subtract days, weeks or months from a date.

Everyday

Random Number Generator

Generate random numbers in a range, with optional uniqueness.

Marketing & SEO

Meta Tag Generator

Generate SEO meta tags — title, description, keywords, robots, canonical and viewport.

Marketing & SEO

Open Graph Generator

Build Open Graph and card tags for rich link previews on social platforms.

Marketing & SEO

UTM Campaign Builder

Build trackable campaign URLs with UTM parameters.

Marketing & SEO

SERP Snippet Preview

Preview how your title and description appear in search results, with length limits.

Marketing & SEO

Keyword Density Analyzer

Analyze keyword frequency and density in your content.

Marketing & SEO

Robots.txt Generator

Create a robots.txt with allow / disallow rules and a sitemap reference.

Marketing & SEO

XML Sitemap Generator

Turn a list of URLs into a valid XML sitemap.

Marketing & SEO

Hashtag Generator

Turn keywords into clean, deduplicated hashtags.

Marketing & SEO

Social Character Counter

Count characters against common post, caption and bio length limits.

Marketing & SEO

CTR Calculator

Calculate click-through rate from clicks and impressions.

Marketing & SEO

Conversion Rate Calculator

Work out conversion rate from conversions and visits.

Marketing & SEO

CPM, CPC & CPA Calculator

Calculate CPM, CPC and CPA from spend, impressions, clicks and conversions.

Marketing & SEO

ROAS Calculator

Measure return on ad spend from revenue and cost.

Marketing & SEO

Engagement Rate Calculator

Compute engagement rate from interactions and audience size.

Marketing & SEO

A/B Test Significance Calculator

Check whether an A/B test conversion result is statistically significant.

Marketing & SEO

Email Signature Generator

Create a clean HTML email signature you can copy into your mail client.

Aviation

Density Altitude Calculator

Density altitude from pressure altitude, temperature and optional dewpoint — runs in your browser.

Aviation

Wind Correction Angle Calculator

Solve the wind triangle: wind correction angle, true heading and ground speed from TAS, course and wind.

Aviation

True Airspeed (TAS) Calculator

Convert calibrated airspeed to true airspeed and Mach from pressure altitude and temperature.

Aviation

Crosswind Component Calculator

Headwind, tailwind and crosswind components for any runway and wind — runs in your browser.

Aviation

METAR Decoder

Paste a METAR or SPECI and read it in plain English: wind, visibility, weather, clouds, temperature, altimeter and flight category.

Aviation

TAF Decoder

Paste a TAF forecast and see each FM, TEMPO, BECMG and PROB period decoded into a plain-English timeline.

Aviation

Cloud Base Calculator

Estimate the cloud base from temperature and dew point (°C or °F), with relative humidity. For training and planning.

Aviation

Pressure Altitude Calculator

Work out pressure altitude from field elevation and altimeter setting in inHg or hPa (QNH), with the rule-of-thumb check.

Aviation

Flight Time & Fuel Calculator

Distance and ground speed to flight time, plus trip fuel and 30 or 45 minute reserve in gallons, litres or pounds.

Aviation

Weight & Balance Calculator

Enter weights and arms from your POH to get total weight, moment and centre of gravity, checked against your limits.