A curated collection of useful free online tools and calculators that work directly in your web browser.
- Calculators
- Date & Time
- Converters
- Developer Tools
- Text Tools
- Generators
- Finance Tools
- Health & Fitness
- Image Tools
- PDF Tools
- Productivity Tools
- Calculator.net - Large collection of financial, health, math, time, and everyday calculators.
- Omni Calculator - Extensive collection of calculators covering science, finance, health, and everyday calculations.
- Wolfram Alpha - Computational knowledge engine for mathematics, science, and many other subjects.
- DateCalx - Free online calculators for dates, age, business days, countdowns, calendars, and time.
- WattsCalc - Free wattage and electricity cost calculator for appliances and devices.
- Lawn Mowing Cost Calculator - Free calculator for lawn mowing cost estimates by area, rate, and extras.
- Embroidery Pricing Calculator - Free embroidery job pricing from stitches, fabric, and labor.
- WorkroomCalc - Free Roman blind calculator for fabric, lining, rods, rings, and cord estimates.
- DateCalx - Date Difference - Calculate the difference between two dates in days, weeks, months, and years.
- DateCalx - Age Calculator - Calculate exact age from a date of birth.
- DateCalx - Business Days Calculator - Calculate working days between dates with weekend and public holiday options.
- Time and Date - Date, time zone, calendar, world clock, and time-related tools.
- Calculator.net Date Calculator - Calculate dates, date differences, and related time calculations.
- Google Unit Converter - Quick unit conversions directly through Google Search.
- ConvertUnits - Convert units for length, weight, temperature, area, volume, and more.
- UnitConverters.net - Collection of unit conversion tools covering many measurement categories.
- JSON Formatter - Format, validate, and work with JSON data.
- DevTools - Collection of useful browser-based developer utilities.
- Regex101 - Test and debug regular expressions with detailed explanations.
- CyberChef - Browser-based data analysis, encoding, decoding, and transformation toolkit.
- JSONPath Tester - Test JSONPath expressions against JSON and view every matching value in the browser.
- WordCounter - Count words, characters, sentences, and paragraphs.
- Character Counter - Count characters, words, sentences, and lines.
- Diffchecker - Compare text and identify differences between documents.
- Random.org - Random number and randomization tools.
- QR Code Generator - Create QR codes for URLs, text, and other information.
- 1Password Password Generator - Generate secure random passwords.
- Codex Theme Builder - Free browser theme builder for OpenAI Codex with live preview and CSS token export.
- Image to Crochet Pattern - Free tool that converts images into crochet patterns.
- Investor.gov Calculators - Financial calculators and investing tools from the U.S. Securities and Exchange Commission.
- NerdWallet Calculators - Financial calculators covering loans, mortgages, investments, and personal finance.
- Bankrate Calculators - Financial calculators for mortgages, loans, savings, and other financial decisions.
- Calculator.net Health Calculators - Health and fitness calculators including BMI, calorie, body fat, and related tools.
- Mayo Clinic BMI Calculator - Calculate body mass index.
- TDEE Calculator - Estimate total daily energy expenditure and calorie needs.
- TinyPNG - Compress PNG and JPEG images online.
- Squoosh - Browser-based image compression and optimization tool.
- Remove.bg - Remove backgrounds from images online.
- Adobe Acrobat Online - Browser-based PDF tools for common document tasks.
- iLovePDF - Online tools for merging, splitting, compressing, and converting PDFs.
- Smallpdf - Collection of browser-based PDF tools and converters.
- Notion - Workspace for notes, documents, databases, and project organization.
- Trello - Visual task and project management boards.
- Google Keep - Simple browser-based notes and lists.
- SkyCOTL Tools - Free guides and calculators for Sky: Children of the Light.
- Pressure Washer Fix - Free troubleshooting guides for common pressure washer problems.
Contributions are welcome!
Before submitting a tool, please make sure:
- The tool is publicly accessible.
- The tool provides useful functionality.
- The tool has a free option.
- The URL points directly to the tool or service.
- The description is short and accurate.
- There is no affiliate or promotional tracking link.
- The tool is not already listed.
Add your entry to the most relevant category using this format:
- [Tool Name](https://example.com/) - Short, accurate description of what the tool does.