Annotation Time Calculator

Work out annotation time instantly with clear inputs, formula shown and shareable results.

About Annotation Time Calculator

Annotation schedules slip because planners use nominal working hours rather than productive ones. Effective capacity is annotators multiplied by genuinely productive hours per day — typically six of eight once breaks, guideline lookups and edge-case discussion are removed — and the calendar duration is total work divided by that capacity.

Formula

Schedule

total hours = items x seconds / 3600; daily capacity = annotators x productive hours; days = total hours / daily capacity

Worked example

With the default values below, Annotation Time Calculator returns Working days to finish of 3.9. Change any input above and every figure here is recalculated in your browser.

Inputs used

Items to annotateminimum 1: 20,000
Seconds per itemminimum 1 s: 25 s
Annotators availableminimum 1: 6
Productive hours per annotator per dayaccepts 0.5–12 h: 6 h

Results

Working days to finish: 3.9 days
Total annotator hours: 138.9 h
Items per annotator per day: 864
Team throughput: 864 items/h

Step by step

1Values used
2Schedule
3Working days to finish= 3.9 days
4Total annotator hours= 138.9 h
5Items per annotator per day= 864
6Team throughput= 864 items/h

Assumptions and limits

The result is derived only from the 4 inputs listed above. Anything not among them is not part of the calculation.
In particular, this calculator does not take inflation, tax, fees or charges or compounding frequency into account.
Figures are rounded for display to 1 decimal place, so totals built from several rounded parts can differ slightly from the unrounded arithmetic.

How these calculators are built and tested is described on the Methodology page. If a figure looks wrong, please report it.

Frequently Asked Questions

Why not use eight productive hours?

Sustained annotation is fatiguing and quality falls sharply after a few hours. Teams that plan on eight hours routinely finish late and with worse agreement.

Does adding annotators scale linearly?

Only up to a point. Larger teams need more guideline training and more adjudication, and consistency drops, so plan for a modest efficiency loss as the team grows.