NTP Timestamp Converter
Decode NTP seconds and fraction fields with an explicit era, or encode a UTC date/time into an NTP timestamp.
Starts with an editable example. Replace the dates and rules with your own.
Your calculation
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Choose your dates.
Select your counting rules and calculate.
Calculation details
| Step | Value |
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How to use this calculator
Enter unsigned 32-bit seconds and fraction fields and select era 0 or 1. Decide whether an all-zero timestamp means unknown or a literal boundary instant.
The fraction denominator is 2^32. The report preserves its exact decimal value and rounds calendar display to nanoseconds. Conversion uses nominal UTC seconds without leap-second or smear reconstruction.
A worked example
Era 0, seconds 2208988800 and fraction 2147483648 represent January 1, 1970 at 00:00:00.5 UTC.
Why must I choose an era?
The 32-bit seconds field wraps. Era 1 begins February 7, 2036 at 06:28:16 UTC, so the wire fields alone cannot identify the full date.
Which calendar and years are supported?
Each result states its calendar, time scale, precision and supported range. Batch converters accept up to 100 nonempty input lines and retain invalid rows. Copy, CSV and print include the calculation rules. Calendar downloads appear when a result contains dated events. Calculations run in your browser; no reminders or jobs are scheduled.
What happens to my dates?
Calculations run on your device. Saving a calculation is optional and keeps it in this browser. A setup link contains the dates and settings you entered; anyone with the link can read them. Use one tab per saved calculator. Clear saved data from Privacy & settings.