Find the weekday for any Gregorian date — plan anniversaries, verify old records, settle bets. Check what day you were born in seconds — free, no signup, runs locally.
Content reviewed October 2026 · About Toolzum
Get ISO week numbers for any date — plan sprints and fiscal weeks correctly. Know Week 32 means late July instantly — free, local, no signup.
Convert any date to its day-of-year number (1–365/366) with days remaining. Developers compute ordinal dates for logs and filenames — free, no signup, runs locally.
Raise any base to any power — squares, cubes, negative and fractional exponents with full precision. Students check 2^10 = 1024 homework in seconds — free, no signup, runs locally.
Calculate exact age in years, months, and days from day-month-year dropdowns with a target date. Includes eligibility check for Indian government age requirements.
Convert Unix timestamps to human-readable dates and back. Shows UTC, ISO 8601, locale, date, and time formats. Milliseconds, seconds, and ISO 8601 convert both directions with timezone clarity — local math, free, no signup.
Enter your birth date: someone born 15 August 1995 gets Tuesday instantly. Works for any Gregorian calendar date, past or future — planning a 10th anniversary lands on the exact weekday.
Any Gregorian date the input accepts, centuries back or forward. Pre-1582 dates predate Gregorian adoption in most countries, so treat very old results as proleptic (mathematical extension).
Enter the 13th of each month one by one — a year holds one to three Friday the 13ths. Checking all twelve takes under a minute.
No — the calculation runs entirely in your browser. No dates leave your device and no account is needed.