Project Time Calculator
Work out any craft project in hours, sessions and weeks from your own measured working rate.
At a glance
- What you enter
- Work to do, Your working rate, Efficiency factor, Finishing allowance, Hours in one session, Sessions per week, How many projects, Weeks available
- What you get
- Total work, Hours at your measured rate, Hours with the efficiency factor, Hours of finishing, Total hours, Sessions to finish, Weeks to finish at your pace, Calendar days, Hours you can give it in a week, Hours short of the deadline, Hours to spare, Rate required including your efficiency and finishing, The plan fits the deadline, Your rate against the rate required
- Formula shown
- Yes, every step, right below your results.
- Cost and privacy
- Free, no account needed, and nothing you type is stored.
See worked examples ↓ Read the FAQ ↓ Share this calculator ↓
Results are estimates for general information only, always verify with a professional or official source before acting on them.
How to use the Project Time Calculator
- 1 Enter Work to do (units), The whole project in one unit: square centimetres, rows, stitches, beads, pots, metres.
- 2 Enter Your working rate (units per hour), Measure it: time a full hour of ordinary work on this project and divide the output by the time.
- 3 Enter Efficiency factor (times), One for a plain repeat, 0.6 to 0.8 for colour changes, shaping or a first attempt at the technique.
- 4 Enter Finishing allowance (%), Blocking, pressing, seaming, mounting, framing, sanding. Ten to twenty five percent is usual.
- 5 Enter Hours in one session (h), The length you actually keep up, not the length you would like to.
- 6 Enter Sessions per week (sessions), How many sittings you realistically get in a normal week.
- 7 Enter How many projects, For a batch or a set, such as six of the same item.
- 8 Enter Weeks available (weeks), Optional. Leave at zero and the tool simply reports how much time you do not have.
- 9 Press Calculate. You get Total work, Hours at your measured rate, Hours with the efficiency factor, Hours of finishing, Total hours, Sessions to finish, Weeks to finish at your pace, Calendar days, Hours you can give it in a week, Hours short of the deadline, Hours to spare, Rate required including your efficiency and finishing, The plan fits the deadline, Your rate against the rate required, and every intermediate step stays visible under "How is this calculated?"
- 10 Change one number at a time to see what moves the result, that is usually the most useful thing a calculator can tell you.
Worked examples
Real numbers run through this calculator. Open any example to load it into the form above and change it.
An embroidery panel
Four thousand square centimetres at 40 per hour, 1.5 hour sessions.
You enter
- Work to do
- 4,000 units
- Your working rate
- 40 units per hour
- Efficiency factor
- 0.85 times
- Finishing allowance
- 15%
- Hours in one session
- 1.50 h
- Sessions per week
- 4 sessions
- How many projects
- 1
- Weeks available
- 0 weeks
You get
- Total work
- 4,000.00 units
- Hours at your measured rate
- 100.00 h
- Hours with the efficiency factor
- 117.65 h
- Hours of finishing
- 17.65 h
- Total hours
- 135.29 h
- Sessions to finish
- 91
- Weeks to finish at your pace
- 22.75 weeks
- Calendar days
- 159.25 days
- Hours you can give it in a week
- 6.00 h
- Hours short of the deadline
- 0.00 h
- Hours to spare
- 0.00 h
- Rate required including your efficiency and finishing
- 0.00 units per hour
- The plan fits the deadline
- 0
- Your rate against the rate required
- 0.00
A hundred hours at the measured rate, 117.6 with the efficiency factor and 135 with finishing, so 90 sessions and about 22.5 weeks at four sessions a week.
Six of the same item for a market
Six pieces of 300 units at 25 per hour, a deadline eight weeks away.
You enter
- Work to do
- 300 units
- Your working rate
- 25 units per hour
- Efficiency factor
- 0.80 times
- Finishing allowance
- 20%
- Hours in one session
- 2 h
- Sessions per week
- 5 sessions
- How many projects
- 6
- Weeks available
- 8 weeks
You get
- Total work
- 1,800.00 units
- Hours at your measured rate
- 72.00 h
- Hours with the efficiency factor
- 90.00 h
- Hours of finishing
- 18.00 h
- Total hours
- 108.00 h
- Sessions to finish
- 54
- Weeks to finish at your pace
- 10.80 weeks
- Calendar days
- 75.60 days
- Hours you can give it in a week
- 10.00 h
- Hours short of the deadline
- 28.00 h
- Hours to spare
- -28.00 h
- Rate required including your efficiency and finishing
- 33.75 units per hour
- The plan fits the deadline
- 0
- Your rate against the rate required
- 0.74
86.4 hours in total, and 80 hours available before the deadline, so the plan is six hours short. Ten sessions a week would be needed instead of five.
A batch with room to spare
Two pieces at 1,200 units, a session pattern of three sessions a week.
You enter
- Work to do
- 1,200 units
- Your working rate
- 60 units per hour
- Efficiency factor
- 0.90 times
- Finishing allowance
- 10%
- Hours in one session
- 2 h
- Sessions per week
- 3 sessions
- How many projects
- 2
- Weeks available
- 6 weeks
You get
- Total work
- 2,400.00 units
- Hours at your measured rate
- 40.00 h
- Hours with the efficiency factor
- 44.44 h
- Hours of finishing
- 4.44 h
- Total hours
- 48.89 h
- Sessions to finish
- 25
- Weeks to finish at your pace
- 8.33 weeks
- Calendar days
- 58.33 days
- Hours you can give it in a week
- 6.00 h
- Hours short of the deadline
- 12.89 h
- Hours to spare
- -12.89 h
- Rate required including your efficiency and finishing
- 81.48 units per hour
- The plan fits the deadline
- 0
- Your rate against the rate required
- 0.74
48.9 hours over 25 sessions, which is 8.3 weeks at three sessions a week, so six weeks is not enough but ten is comfortable.
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