WHALETU TOOL COLLECTION
Calculators & Converters
Transparent everyday, finance, date and unit calculations.
◉ Local-first15 available toolsNo account
Each tool page states exact accepted formats and limits before processing.
Files and text are excluded from analytics events. Heavy modules load only when needed.
A practical path through calculators work
CalculatorsPopular
Scientific Calculator
Evaluate arithmetic expressions with functions and constants.
CalculatorsPopular
Percentage Calculator
Calculate a percentage of any value.
Calculators
BMI Calculator
Calculate body mass index from metric measurements.
Calculators
Age Calculator
Calculate exact age from a date of birth.
CalculatorsPopular
Loan Calculator
Estimate monthly loan payments and total interest.
Calculators
Time Converter
Convert between seconds, minutes, hours and days.
Calculators
Temperature Converter
Convert Celsius, Fahrenheit and Kelvin.
Calculators
Length Converter
Convert metric and imperial length units.
Calculators
Data Size Converter
Convert bytes, KB, MB, GB and TB.
Calculators
Roman Numeral Converter
Convert decimal numbers and Roman numerals.
Calculators
Number Base Converter
Convert integers between binary, octal, decimal and hexadecimal.
CalculatorsProfessional workspace
Compound Interest Calculator
Estimate compound growth with periodic contributions and annual detail.
CalculatorsProfessional workspace
Mortgage & Amortization Calculator
Calculate fixed-rate payments, totals and a monthly amortization schedule.
CalculatorsProfessional workspace
Date Difference Calculator
Calculate calendar years, months, days and total days between two dates.
CalculatorsProfessional workspace
Time Zone Converter
Convert a date and time between IANA time zones with daylight-saving rules.
Tools that explain their limits
Every workspace is built around a clear input, visible processing state, useful result and recoverable error path. When a task can run safely in the browser, it stays on your device.
Are files uploaded?
Tools marked Local, Local with limits or Local + downloaded code do not upload tool content. Ordinary page requests may still appear in access logs.
Why do some tools load extra code?
PDF, image, schema and archive workflows load specialized modules only when their workspace opens, keeping category pages fast.