Formula
- Use the units shown beside each field.
- Results update automatically whenever you change an input.
- Displayed values use up to four decimal places, or scientific notation for very small or large numbers. Calculations use standard floating-point arithmetic; exact integer and fraction tools identify their own precision rules.
- Uses already determined schedule windows; does not build a dependency network. Negative float indicates a missed constraint.
Example Calculation
- Earliest start: 2 days
- Earliest finish: 5 days
- Latest start: 4 days
- Latest finish: 7 days
Early window 2–5 and late window 4–7 imply duration 3 and float 2 days.
Frequently asked questions
How do I use this calculator?
Enter earliest start, earliest finish, latest start, latest finish. The result updates automatically. Use Reset to restore the example values.
What method does it use?
total float=latest start−earliest start=latest finish−earliest finish.. Uses already determined schedule windows; does not build a dependency network. Negative float indicates a missed constraint.
Why might a rounded result differ?
The calculation keeps full numeric precision internally, then rounds the displayed result. Rounding intermediate steps by hand can produce a slightly different answer.
Are my inputs saved online?
No. This calculator processes your inputs in your browser. A recently used list stores only calculator names on this device, not your entered values.
Check the assumptions and units before using this result. Read about calculation methods.