Math & Dates

Work with timestamps, calculations, and human-friendly dates.

15 tools in this category

Move between Unix timestamps and readable UTC or local dates.

Calculate exact elapsed time between two dates or timestamps.

Convert a local date-time between IANA time zones with DST awareness.

Validate five-field cron schedules and preview the next five UTC runs.

Calculate percent of a value, percentage rate, or percentage change.

Solve a/b = c/d for one unknown using cross multiplication.

Calculate arithmetic mean, median, mode, sum, and range endpoints.

Find exact greatest common divisors and least common multiples.

Compute exact factorials with arbitrary-precision integer arithmetic.

Generate exact indexed Fibonacci terms starting with F(0) = 0.

Test integer primality and show factors for composite numbers.

Estimate compound growth from principal, rate, time, and frequency.

Calculate remaining time and estimated completion from downloaded, total, and rate values.

Evaluate arithmetic and selected functions with a recursive-descent parser, never eval.

Measure elapsed time with pause, resume, reset, and precise lap tracking.