Free Tools

Free Time & Date Calculators

Age calculator, date difference, GPA, random numbers — accurate, instant, and free. Use them for planning, school, or just curiosity.

Tools that answer questions like “how old will I be on Jan 1, 2030?”, “how many business days until launch?”, “what grade do I need on my final to keep an A?”, and “pick a random name from this list.” Pure math, no signup, no nonsense.

Frequently Asked Questions

How do these calculators handle leap years?
All date calculations use the JavaScript Date object, which handles leap years (every 4 years, except century years not divisible by 400) automatically. Feb 29 exists in 2024, 2028, 2032; not in 2100. The age and date calculators count actual elapsed calendar days, so leap years are reflected in the totals.
What time zone do these use?
They use your local time zone (read from your browser). For most everyday use this is what you want — your "today" is your today. If you need UTC or another zone, manually adjust your input dates.
Is the random number generator truly random?
It uses crypto.getRandomValues() — the browser's cryptographically secure random source. This is the same primitive used for security-sensitive applications (key generation, password generation). Pseudo-random Math.random() would be predictable; we don't use it.
What's a typical use case for the date calculator?
Project deadlines (how many business days from today to launch?), legal/financial dates (90 days from contract signing), birthday counts, "how long until X" curiosity, or working back from a target date to figure out when to start.
How accurate is GPA calculation?
It uses the standard 4.0 unweighted scale (A=4.0, B=3.0, C=2.0, D=1.0, F=0). For weighted GPAs (honors/AP/IB bonuses), most schools add +0.5 or +1.0 to the base — adjust your inputs if your school weights. The "grade needed on final" mode lets you reverse-engineer the score required to hit a target final grade.