BMI Calculator
Calculate your Body Mass Index and its WHO classification.
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Health calculators, converters, generators and financial tools. All in your browser, no data sent.
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Health
BMI, calories, ovulation and pregnancy calculators. Tools to take care of your wellbeing.
Converters
Convert measurement units, currencies and colors from one format to another instantly.
Generators
Generate secure passwords, QR codes and cryptographic hashes online.
Finance
VAT, compound interest and more calculators to get your accounts in order.
All tools
Calculators, converters, generators and financial tools. Free, no sign-up, no intrusive ads.
Unit Converter
Convert length, mass, temperature and volume.
Currency Converter
Convert EUR, USD, GBP, MXN and more with reference rates.
Color Converter
Convert HEX, RGB and HSL with a live preview.
Password Generator
Generate secure passwords from 8 to 64 characters.
QR Code Generator
Generate QR codes from any text or URL.
Hash Generator
Compute SHA-256 and MD5 locally in your browser.
Body Fat Calculator
Estimate your body fat percentage with the US Navy method.
Daily Water Intake Calculator
How much water to drink based on your weight and activity.
Heart Rate Zones Calculator
Calculate your training zones with Karvonen.
Speed Converter
Convert km/h, mph, m/s and knots instantly.
Digital Storage Converter
Convert GB, MB, TB and binary units (KiB, MiB).
Time Converter
Convert hours, minutes, seconds, days and more.
UUID Generator
Generate version 4 universally unique identifiers.
VAT Calculator
Add or remove VAT (21%, 10%, 4%) from any amount.
Compound Interest Calculator
Simulate the growth of your savings or investment.
Roman Numerals Converter
Convert numbers to and from Roman numerals.
Base64 Encoder and Decoder
Encode and decode text in Base64.
Date Difference Calculator
Calculate the days, months and years between two dates.
Sleep Calculator
Find the ideal bedtime to wake up between full sleep cycles.
Calories Burned Calculator
Estimate how many calories you burn during daily activities based on your weight and duration.
Ideal Weight Calculator
Calculate your ideal weight using several classic methods: Robinson, Miller, Devine and Hamwi.
Numbers to Words
Convert any number to its written form in words, in Spanish or English.
Numeric Base Converter
Convert numbers between bases: binary, octal, decimal, hexadecimal and up to base 36.
Age Calculator
Calculate your exact age in years, months and days, and how many days you have lived.
Character and Word Counter
Count characters, words, letters, numbers and lines of any text instantly.
Timestamp Converter
Convert Unix timestamps to readable dates and times and vice versa.
Percentage Calculator
Calculate X% of a number, what percentage A is of B, and the change between two values.
Tip Calculator
Calculate the tip, the total with tip and how much each person at the table pays.
Simple Interest Calculator
Calculate the simple interest and final amount of an investment or loan.
Random Number Generator
Generate random numbers within a range, with the option of no repeats.
Barcode Generator
Generate Code 39 barcodes from any text, ready to download.
Lorem Ipsum Generator
Generate classic lorem ipsum filler text for mockups, templates and web designs.
Loan and Amortization Calculator
Calculate monthly payment, amortization schedule and total payable (French, German, American systems).
JWT Generator
Generate signed JSON Web Tokens (HS256, HS384, HS512) for development and testing.
JSON Formatter and Minifier
Format, minify, validate and sort keys of any JSON instantly.
Regular Expression Tester (Regex)
Test, debug and understand your regex with match highlighting, groups and token-by-token explanation.
Macros and Nutrients Calculator
Calculate your macros (carbs, protein, fat) and target calories based on goal, weight and activity.
Date Format Converter
Convert dates between formats: ISO 8601, RFC 2822/3339, Unix, SQL, European, US and custom.
Inflation and Purchasing Power Calculator
Calculate how inflation erodes money's value over time (forward, backward or cumulative).
Latest articles
Numeric Bases: Binary, Octal, Decimal and Hexadecimal
What a numeric base is and how binary, octal, decimal and hexadecimal work. Convert between bases with examples, an equivalence table and practical tips.
3 min readHow to Calculate the Difference Between Two Dates (Days, Weeks, Months and Business Days)
Calculate how many days are between two dates, how to count business days, when it is useful (deadlines, vacations, projects) and how to use our tool.
3 min readHow to Calculate the Exact Age in Years, Months and Days
Calculate your exact age in years, months, days, weeks and totals. How real date subtraction works, how leap years matter, and fun facts with examples.
3 min readHow to Convert Numbers to Words: A Quick Guide
Learn how to convert numbers to words for checks, invoices and contracts. See how the conversion works, the differences between Spanish and English, and the tool's limits.
3 min readCharacter and Word Counter: A Practical Text Guide
What a character and word counter counts: characters, words, letters, numbers and lines. Check Twitter, SMS and SEO limits and learn how to use it.
3 min readDate Format Converter: ISO, Unix, RFC, SQL and more
Convert dates between ISO 8601, RFC 2822/3339, Unix timestamp, SQL, EU/US format and custom. Standard tokens. Free.
3 min readRoman Numerals: How to Read and Convert Them (Table 1–3999)
Learn the rules to read and write Roman numerals, the 1–3999 table, the most common mistakes (IIII, VV) and how to convert instantly with our tool.
2 min readWhat is a Timestamp and How to Convert it to Date and Time
Learn what a Unix timestamp is, the difference between seconds and milliseconds, where it is used, and how to convert it to a readable date.
3 min read