Precision Timing
Online Stopwatch and Timer
Millisecond-accurate timing with drift-free math, unlimited lap splits and a one-click results summary you can copy or share.
Laps
0 recordedNo laps yet. Press Lap while the stopwatch runs to record your first split.
Keep exploring
More Time Tools
Every ClockMatrix utility in one grid — jump straight to the tool you need.
Christmas Countdown
Live days, hours and seconds until December 25th.
Open tool →New Year Countdown
Count down to midnight on January 1st, every year.
Open tool →Stopwatch Timer
Precision stopwatch with laps and millisecond readout.
Open tool →Pomodoro Timer
Focus and break cycles with a persistent session count.
Open tool →Time Zone Converter
Compare any two zones side by side with live offsets.
Open tool →Countdown Builder
Create a custom countdown to any date and time.
Open tool →Countdown Hub
Browse 5,000+ live event countdowns grouped by category.
Open tool →Age Calculator
Exact years, months and days old, plus a birthday countdown.
Open tool →Days Between Dates
Calendar and working-day span between any two dates.
Open tool →Sleep Calculator
Best bedtimes and wake times across 90-minute sleep cycles.
Open tool →Meeting Planner
Compare time zones side by side and find the overlap window.
Open tool →Time Guides
Browse the full guide library by category, event, city and year.
Open tool →Reference
Stopwatch Timing, Explained
How ClockMatrix keeps millisecond timing drift-free — and the rules behind splits, time zones and leap years.