Time.ms
Precise atomic time
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Loading date...

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Connecting to atomic clock...
Time
Device Time
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Atomic Time
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Time Offset
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Timezone
Time Zone
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UTC Offset
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Other Info
UTC Time
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Unix Time
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Network
IPv4
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IPv6
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ISP Provider
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ASN
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Network Delay
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Location
Location (Network)
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Location (Device)
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Frequently Asked Questions

How accurate is Time.ms?
Time.ms provides exact time with millisecond-precise atomic clock synchronization via global network infrastructure. The actual accuracy depends on your network latency, typically achieving synchronization within ±5-50 milliseconds. The system continuously calculates and displays the Round-Trip Time (RTT) and synchronization precision for full transparency.
What is atomic clock time?
Atomic clocks are the most accurate time-keeping devices, using the vibrations of atoms to measure time. They form the basis of Coordinated Universal Time (UTC) and are synchronized globally. Time.ms connects to reliable time sources that maintain synchronization with atomic clock networks, bringing this precision to your browser.
What is RTT (Round-Trip Time)?
RTT measures the time it takes for a signal to travel from your device to the time server and back. Time.ms uses RTT to compensate for network delays, calculating the actual time by adding half the RTT to the server timestamp. Lower RTT values indicate better synchronization accuracy.
How does Time.ms detect my location?
Time.ms uses advanced network infrastructure to detect your approximate location based on your IP address. This provides city-level accuracy without requiring GPS permissions. The location data is used to display your local timezone and calculate UTC offset. No personal information is stored or tracked.
What do the different time formats mean?
Unix Timestamp: Seconds since January 1, 1970 UTC - used by computers worldwide
ISO 8601: International standard format (YYYY-MM-DDTHH:mm:ss.sssZ)
UTC Time: Coordinated Universal Time - the global time standard
Local Time: Your current timezone's time
Click on any time display to cycle through different formats.
How can I use Time.ms for time synchronization?
Time.ms shows the exact offset between your device clock and atomic time. Use the "Time Offset" value to adjust your system clock manually, or click the copy button next to any time display to get the precise timestamp. The "Clock Drift" metric shows how fast your device clock is gaining or losing time.
What are the interactive features?
Click the date: Cycle through different date/time formats
Click the time (HH:MM:SS): Enter fullscreen mode for focused time display
Click milliseconds: Toggle blur effect for users sensitive to rapid changes
Copy buttons: Click to copy any time value to clipboard
Info icons: Hover or click for detailed explanations of technical terms
How can I make my computer have this accurate time?
You can synchronize your computer with accurate time by using a reliable NTP (Network Time Protocol) service. NTP is a networking protocol designed to synchronize clocks between computer systems over the internet. For optimal accuracy, we recommend using time.cloudflare.com as your NTP server. You can find detailed setup instructions for various operating systems at: https://developers.cloudflare.com/time-services/ntp/usage/
How is the synchronization accuracy calculated?
Time.ms uses a scientific approach to calculate realistic accuracy estimates by considering multiple sources of uncertainty. Unlike simple methods that only use half the network round-trip time (RTT÷2), our calculation combines four independent error sources using statistical methods: Network Uncertainty (40% of RTT accounting for network asymmetry and jitter), Measurement Uncertainty (statistical variation from multiple samples), System Uncertainty (browser and OS clock resolution limits), and Connection Quality (based on time drift stability). These uncertainties are combined using the root sum of squares method to provide honest, scientifically-sound precision estimates that reflect real-world synchronization accuracy.
Is Time.ms free to use?
Yes, Time.ms is completely free to use with no registration required. It's a public service providing accurate time information to anyone who needs it. The service runs on high-performance global network infrastructure, ensuring reliable availability and low latency worldwide.