Free Online Calculators and Utilities
Fast, simple tools for finance, dates, health, conversions, and more.
Everyday calculations, done instantly
Tooler's utilities cover the calculations and conversions you reach for most often — loan payments, tax math, body metrics, date differences, unit conversions, text formatting, and developer tools. Each utility is built for speed: enter your inputs, get your result, and move on. No sign-up, no page reloads, no clutter.
Unlike ad-stuffed calculator sites, every Tooler utility includes educational content explaining how the result is calculated, what the numbers mean, and common mistakes to avoid. Whether you are comparing home loan offers, preparing a GST invoice, checking your BMI, or generating a QR code — you get the answer and the context in one place.
Most popular
The utilities people use the most.
How to choose the right tool
Finance & Tax
Use the EMI Calculator to compare loan offers and plan repayments. Use GST Calculator to add or remove tax from invoices. The Percentage Calculator handles discounts, markups, and growth rates. The Currency Converter gives quick indicative exchange rates.
Health & Dates
BMI Calculator screens weight categories. Calories Calculator estimates daily energy needs (BMR & TDEE). Age Calculator gives exact age in years, months, and days. Date Difference counts days between any two dates.
Text & Writing
Word Counter checks counts and reading time. Case Converter switches between naming conventions. Text Decorator styles social bios with Unicode. Text to ASCII creates retro banners. Symbol Picker copies special characters.
Developer Tools
Hash Generator creates checksums and digests. Base64 encodes and decodes text. Base Converter switches between binary, octal, decimal, and hex. QR Code Generator creates scannable QR codes from any text or URL.
Finance and Tax
Loan EMI Calculator
Calculate monthly loan payments, total interest, and total repayment across India, US, Canada, UK, and Europe.
Sales Tax / VAT / GST Calculator
Add or remove sales tax, VAT, or GST for India, US, Canada, UK, and Europe.
Percentage Calculator
Calculate percentage value, increase/decrease, and percent change instantly.
Currency Converter
Convert between major world currencies using indicative exchange rates.
Health and Dates
BMI Calculator
Calculate Body Mass Index with category classification.
Calories Calculator
Estimate daily calorie needs (BMR and TDEE) based on age, sex, weight, height, and activity level.
Age Calculator
Calculate exact age in years, months, and days from date of birth.
Date Difference Calculator
Find the exact difference between two dates in days, weeks, months, and years.
Astrology
Unit Converters
Length Converter
Convert between meters, kilometers, miles, feet, inches, centimeters, and more.
Weight and Mass Converter
Convert between kilograms, pounds, grams, ounces, tons, and other weight units.
Temperature Converter
Convert between Celsius, Fahrenheit, and Kelvin instantly.
Speed Converter
Convert between km/h, mph, m/s, knots, and other speed units.
Data Storage Converter
Convert between bits, bytes, KB, MB, GB, TB, and more.
Text and Writing
Word Counter
Count words, characters, sentences, and estimated reading time.
Case Converter
Convert text to UPPERCASE, lowercase, Title Case, or Sentence case.
Text Decorator
Style your text with Unicode bold, italic, script, monospace, and other fancy fonts.
Text to ASCII Art
Convert plain text into monospaced ASCII art banners.
Image to ASCII Art
Convert an uploaded image or image URL into grayscale ASCII art.
Symbol Picker
Browse and copy non-keyboard symbols, special characters, arrows, math symbols.
Developer Tools
Hash Generator
Generate MD5, SHA-1, SHA-256, and SHA-512 cryptographic hashes.
Base64 Encode / Decode
Encode text to Base64 or decode Base64 strings back to plain text.
Number Base Converter
Convert numbers between binary, octal, decimal, and hexadecimal.
QR Code Generator
Generate a QR code from any URL, text, or message instantly.
Why use Tooler utilities?
- No sign-up required. Every utility works immediately — open the page, enter your data, get the result.
- Educational, not just functional. Each utility includes explanations, examples, tips, and common mistakes so you understand the output.
- Privacy-first. No data is stored. Calculator inputs are processed in memory and discarded immediately.
- Country-aware. EMI and GST calculators support India, US, Canada, UK, and Europe with local currencies and tax names.
- Fast and reliable. Built on Rails with server-side computation. Results appear instantly without page reloads.
Frequently asked questions
Are Tooler utilities free?
Yes. All calculators and utilities are completely free. No premium tiers, no credit card required, no usage limits.
Are the calculations accurate?
Calculators use standard formulas (Mifflin-St Jeor for calories, reducing-balance for EMI, WHO thresholds for BMI). They produce estimates for educational use — always verify financial or medical decisions with a qualified professional.
Is my data stored?
No. Utility inputs are processed in memory and never stored. We do not log your numbers, share them, or use them for any purpose.