ETA calculator
Work out the remaining time, expected finish time, progress and required speed from a total workload, completed amount, start time and speed (or two timestamps).
Runs in your browserEvery computation happens in your browser — your data never leaves this device.
Fill in the workload, completed amount and times to see the estimate
What this tool does
- Enter a total workload, how much is done and when the job started, and get the remaining time plus an expected finish timestamp.
- For long-running work such as data migrations, bulk imports or video transcoding, use the elapsed-time mode to derive the current rate and check whether progress looks sane.
- Add an optional target finish time to see whether your current speed is enough — the tool reports the rate you would need per second.
- Share the result with teammates: a concrete remaining time and finish timestamp beats "it should be done soon" in any ticket.
Example
Input
Total 1000, completed 400, start 2026-01-01 09:00, current 2026-01-01 10:00 (speed derived from elapsed time)
Output
Remaining 1h 30min; expected finish 2026-01-01 11:30:00; progress 40.0%; derived speed 0.1111 units/s; remaining workload 600
Speed = completed ÷ elapsed = 400 ÷ 3600 s ≈ 0.1111 units/s, and 600 ÷ 0.1111 ≈ 5400 s, which is exactly 1 hour 30 minutes.
Frequently asked questions
What is the difference between "from speed" and "from elapsed time"?
From speed means you supply the units completed per second, which fits stable rates like bandwidth or QPS. From elapsed time derives the rate as completed ÷ elapsed, which fits the "ran for an hour, finished 400 rows" case. The derived mode cannot work when nothing is completed yet — enter the speed instead.
Why does the expected finish differ from my own calculation?
Two usual reasons: times are parsed in your browser local timezone, so collaborators in another zone see different clock values; and the speed is an average over the whole elapsed period, so an early burst makes the estimate optimistic.
Does the remaining time update on its own?
No. This is a one-shot calculation — it runs whenever you change an input. To sharpen the estimate, refresh the "current time" field and calculate again so the average speed covers the newest data.
What happens when nothing is completed, or everything is?
When completed equals the total, the tool reports "all done" and treats remaining time and required speed as zero. When nothing is completed yet, the derived-speed mode has no data, so the tool asks you to enter the speed directly.
Does it need a network connection or upload my numbers?
No. All arithmetic happens in your browser and nothing is sent anywhere, so it also works offline.
Keywords：eta剩余时间预计完成进度速度工作量estimateprogressremaining time