COLLECTION / 02
General tools
Everyday calculators and utilities for conversions, timers, dates, percentages, currency, and purchasing power.
Popular / everyday
Popular general tools
Unit conversion
Unit converter
Convert common length, mass, temperature, area, volume, and speed units in one focused workspace.
Time & date
Timer & stopwatch
Run a clean countdown or stopwatch with pause, resume, and reset controls.
Time & date
Date difference & age
Find elapsed days, calendar time between two dates, or age on a chosen date.
Everyday math
Percentage calculator
Find a percentage of any value and see the same value after an increase or decrease.
Everyday math
Tip & bill split
Calculate a tip, total bill, and equal per-person share for any group size.
Money
Currency converter
Convert common currencies with a clearly dated reference exchange rate.
Money
U.S. inflation
Compare the purchasing power of U.S. dollars between years using CPI reference data.
Collection map
Browse by topic
Topics group the collection into unit conversion, time and date, everyday math, and money tools.
Unit conversion
Move between metric, imperial, temperature, volume, speed, and other common units.
1 tool02Time & date
Run timers and work with ages, dates, durations, and calendar intervals.
2 tools03Everyday math
Solve percentages, splits, comparisons, and recurring day-to-day math.
2 tools04Money
Compare currency, inflation, purchasing power, and common money scenarios.
2 toolsData sources
Calculation and reference data
Converters, percentages, dates, and timers run in your browser. Currency and inflation tools show the source date beside the result so a reference value never pretends to be live market data.
How CalcDB handles sources