Show decimals. This has no impact on the calculation; it is only a visual effect. When using colon notation, all decimals are truncated.

Usage notes

• t₀ is the time at which measurement started. Fill in the corresponding progress into p₀. When some time has elapsed, fill out the second set of fields. The tool will linearly extrapolate to calculate the end/finish time.
• Inputs are evaluated as JavaScript to support entering e.g. 23*3600. Only [0-9 :./*+-] is allowed to prevent self-xss.
• A start time in the past works fine if you know what the progress was back then. You can enter it as negative value, or use the wall clock time from 2 hours ago.

Colon notation

• For convenience, it replaces the first colon with +1/60* and the second with +1/3600*, such that hh:mm and hh:mm:ss will parse and the output unit will be that of the largest position (hours in the case of hh:mm:ss).
• Entering 0:5 is interpreted as 0:05.
• Days are not supported: it keeps using powers of 60 when you enter xx:hh:mm:ss.