How to use the deep sleep calculator
Prepare the values for this calculation
Calculate the proportion of an entered sleep period that was recorded as deep sleep. The tool does not infer sleep stages or diagnose sleep quality. Use the formula below to check that it answers your question. Read the input units before transferring figures from a statement, measurement or dataset.
Enter and check each input
- Total sleep duration (hours): enter a value at least 0.01 and no more than 24. Use the unit named in the label or selected above. Do not leave this required field blank.
- Recorded deep sleep (minutes): enter a value at least 0 and no more than 1440 and a whole number. Use the unit named in the label or selected above. Do not leave this required field blank.
The input table gives a complete example. Keep units and time periods consistent across related fields.
Calculate and resolve any input error
Choose Calculate after entering the values. Changes also update the answer after a short pause. If an error appears, follow its message, correct the field and calculate again. Reset restores the example values.
Interpret the answer
Check Recorded deep-sleep proportion first. With the unchanged example inputs, it is 18.75%. Compare the additional metrics with the primary result; each has its own label and unit.
Compare and keep a useful result
For a controlled comparison, keep every other example input unchanged and change Total sleep duration (hours) from 8 to 8.8. The resulting Recorded deep-sleep proportion is 17.05%. This illustrates the equation’s response to that input, rather than a forecast of real events.
Read the chart’s axis labels and data table. A scenario curve changes one stated input while holding the others fixed; it does not add external observations. Use Download graph to save an available chart as a PNG.
Use Copy result or Download CSV to keep the answer. Share tool shares the page address without placing your input values in the URL. Recheck inputs and assumptions before using the result for a decision.
Deep Sleep Calculator formula
Deep-sleep percentage = deep-sleep minutes ÷ total-sleep minutes × 100.
Inputs and units
| Input | Format / range | Example |
|---|---|---|
| Total sleep duration (hours) | minimum 0.01; maximum 24 | 8 |
| Recorded deep sleep (minutes) | minimum 0; maximum 1440; whole number | 90 |
Worked example
Using the example inputs above, the recorded deep-sleep proportion is 18.75%.
- Recorded deep-sleep proportion
- 18.75%
- Deep sleep
- 90 min
- Total sleep
- 480 min
- Other recorded sleep
- 390 min
Results and assumptions
This is arithmetic on entered sleep-stage data only. Sleep-stage estimates from consumer devices are not the same as professionally scored polysomnography, and this page does not define a normal deep-sleep percentage or diagnose sleep quality.
Sources and method references
Fix an input or unexpected result
Total sleep duration (hours) is required. Enter total sleep duration (hours) using the format and bounds in the input table. Zero and an empty field are different: use zero only if it is allowed and represents your data.
If your answer differs from the example, choose Reset and compare every field, including selected units and options. Check percentage versus decimal entry and whether values describe the same period. Round only the final displayed answer when reproducing the formula.
If a discrepancy remains, report the calculator issue with the page address, non-sensitive example inputs, actual result, expected result and a reference for your calculation.