Frequently Asked Questions
Find answers about accuracy, privacy, tools, and more
Accuracy & Time
How accurate is Clock With Second?
±0.001 second precision, synchronized with NIST time servers every 60 seconds.
What is NIST?
National Institute of Standards and Technology - operates official US atomic clocks.
How often does the clock sync?
Every 60 seconds with NIST and Google time servers.
Why more accurate than phone?
Phone clocks drift seconds per day. Our clock corrects drift every 60 seconds.
Privacy & Data
Do you store my personal data?
No. All tools run locally. We never store your alarms or personal data.
Are alarms saved on your servers?
No. All alarms stored locally in your browser only.
Do you use tracking cookies?
No. We use minimal essential cookies only for functionality.
What if I clear browser cache?
Your alarms and settings will be deleted. Save important alarms as backup.
Tools & Features
How many free tools?
50+ completely free tools including alarms, timers, stopwatches, world clocks.
How does Math Alarm work?
Solve an equation to stop the alarm - ensures you're fully awake.
What is Pomodoro Timer?
25 min work + 5 min break. Scientifically proven productivity method.
What sleep tools available?
Sleep cycle calculator, bedtime optimizer, power nap timer, breathing exercises.
Can I use stopwatch for sports?
Yes. Millisecond precision with lap recording for athletes.
What time zones supported?
All 195+ countries with automatic DST adjustment.
Technical
Can I use it offline?
Yes. Install as PWA for offline use. Time sync needs internet.
Does it work on mobile?
Yes. Fully responsive on iOS, Android, tablets, and desktop.
What browsers supported?
Chrome, Firefox, Safari, Edge, Opera, Brave.
Can I embed on my website?
Yes. Free embeddable widgets available.
Is there an API?
Embeddable widgets available. Developer API planned.
Why shows sync delay?
Shows network latency. Displayed time is always accurate.
Account & Access
Need to create account?
No. No registration required. All tools accessible instantly.
Is there premium version?
No. 100% free forever. No premium tiers or hidden fees.
How to save alarm settings?
Automatically saved in browser. Persists until you clear data.
Can I sync across devices?
No. Privacy first - no server storage. Each device has own alarms.