NUMPTi uses a 96-hour day with fixed-length hours and a small overlap window at each hour boundary to avoid a single “hard” tick.
NUMPTi stands for New Universal Metric Partitioned Time — styled as NUMPTi because the trailing lower-case i is part of Time.
Core time units
- Day: 86,400 seconds (unchanged)
- Hour: 900 seconds (96 hours per day, labelled 00–95)
- Minute: 100 seconds
- Second: 0–99 within the minute
Minutes 0–8 + overlap minute 9
Each 900-second hour contains 9 normal minutes (labelled 0–8). The first 100 seconds of each hour can also be labelled as the previous hour’s minute 9.
- Primary label during that window: current hour, minute 0
- Alternate label: previous hour, minute 9
- The ◐ symbol indicates you are looking at an overlap/alternate reading.
Formats
- Brackets:
HH(M)SS e.g. 74(8)01
- Colon:
HH:M:SS (minute is single digit)
Date
The date line uses 10-day weeks in UTC, shown as YYYY(WW.D) where WW is a zero-indexed week number and D is a zero-indexed day within the 10-day week.
Example: 2025(35.6).
UTC, converters, and privacy
- The main clock is global and based on UTC.
- Converters accept Unix time and wall time with a fixed UTC offset.
- Location is only used if you press Use my location. Settings are stored in your browser via localStorage.