About

In high-stakes environments - such as industrial engineering, chemical kinetics, or sprint training - standard browser timers fail due to "tab throttling." Modern browsers reduce resource allocation to inactive tabs to save battery, causing standard counters to lag or stop entirely. This tool solves that problem using a timestamp-delta architecture.

Why this tool is superior: It does not count seconds; it calculates the difference between the t_start timestamp and the t_now timestamp on every single animation frame. This means if your computer freezes for 10 seconds and recovers, the timer jumps to the correct time immediately, maintaining true chronological fidelity. It supports four simultaneous timelines, automated local storage persistence (crash protection), and statistical analysis of split times (Best/Worst/Average).

Formulas

To ensure zero drift over long durations, we utilize the Delta Time calculation method instead of an incremental counter.

{

t_elapsed = t_current − t_start − ∑t_pausest_split = t_elapsed − t_{prev_lap}

For pacing analysis, the tool calculates the Deviation Ratio D against a target T:

D = t_elapsedT_target × 100%

Reference Data

Time Magnitude	Duration (s)	Scientific Context / Benchmark
Planck Time	5.39 × 10^-44	Theoretical limit of measurable time
Attosecond	1.0 × 10^-18	Electron movement scale
Nanosecond	1.0 × 10^-9	CPU clock cycle (1 GHz)
Microsecond	1.0 × 10^-6	High-speed trading latency
Millisecond	0.001	Standard stopwatch precision
Human Blink	0.1 − 0.4	Average eyelid duration
Auditory Reaction	0.17	Human brain processing sound
Visual Reaction	0.25	Human brain processing light
ISO Second	1.0	9,192,631,770 Cs-133 cycles
Mars Day (Sol)	88775.2	≈ 24h 39m 35s
Micro-century	3155.76	≈ 52 minutes (Joke Unit)
GPS Week Rollover	604800	System reset every 1024 weeks
Sidereal Year	31558149.76	Earth's orbit around Sun
Galactic Year	7.25 × 10¹⁵	Sun's orbit around Galaxy center

Frequently Asked Questions

Yes. Unlike simple JavaScript counters that stop when the tab is hidden, this tool uses system clock timestamps. When you return to the tab, it recalculates the exact time elapsed during your absence, ensuring 100% accuracy.

Data Persistence is active by default. The tool saves the start time, pause duration, and lap history of all 4 timers to LocalStorage. Upon reopening, the timers will appear as if they never stopped running.

The display is accurate to within 1-4ms, depending on the screen refresh rate (60Hz vs 144Hz). However, the underlying mathematical calculation preserves precision up to the microsecond level allowed by the browser's performance API.

Yes. You can use the "Copy Laps" button to paste directly into a spreadsheet, or use "Export CSV" to download a file formatted with Lap Number, Split Time, Total Time, and Delta.

Target Mode turns the timer into a visual pacing tool. The background will shift from blue to yellow (approaching) and red (exceeded) based on the target time you set. Useful for speech practice, cooking, or interval training.