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Late-night sports sleep planner · Korea time
Compare time available for sleep when watching all, part or none of a manually entered sports broadcast. Every date and time uses Korea Standard Time (KST).
Watch the match, or save time for sleep?
Enter a broadcast and wake-up schedule to compare time available for sleep when watching all, part or none of it.
Every date and time uses Korea Standard Time (Asia/Seoul · UTC+09:00), in 24-hour format. Overseas local-time conversion and live sports schedules are not supported.
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How to use this KST planner
- Enter the sport, match start date and time, and expected duration or end date and time in Korea Standard Time (Asia/Seoul). This planner does not convert your local time zone.
- Check your intended bedtime and final wake-up date and time. Adjust the target, buffers and partial-viewing method in advanced settings when needed.
- Compare full viewing, partial viewing and skipping the live broadcast. Read the timeline and intervals; changing the assumed delay also refreshes the result and share content.
- Copy the result text or save a share card. Personal bedtime and wake-up times are excluded from the default share content.
This planner estimates time available for sleep; it does not assess sleep quality or stages. General information is available from CDC: About sleep and NIH: Sleep stages.
No login, paid API or automatic match feed is used. See Privacy, About, Contact for service information.
Formula and assumptions
This is time allocation from entered assumptions, not measured sleep or a health recommendation. All options use the same bedtime, final wake time, and sleep-onset buffer. Read interval counts and the longest continuous interval alongside the total.
Why the result can vary
Sport durations, an eight-hour target and 15/10/15-minute buffers are editable calculation examples, not official durations, statistical averages, or personal recommendations. Delays are scenarios, not probability forecasts.
Example
Fictional January 2, 2030 broadcast
Inputs: Korea time: bed Jan 1 23:30, wake Jan 2 07:30, broadcast Jan 2 04:00–06:00, preparation 15min, post-viewing 10min, sleep-onset 15min per interval, target 8h.
Outcome: Skipping: 7h45m. Full viewing: 5h05m, a loss of 2h40m and target shortfall of 2h55m. Watching the first 60min: 6h05m. Setting only sleep-onset to zero gives 5h35m for full viewing.
Cautions
- Only one broadcast and one sleep window of at most 24 hours are supported. Unsupported inputs are not silently shortened.
- The planner does not judge the health equivalence of continuous and split sleep, alertness, driving safety or arriving late. It does not give sleep-cycle, health-score, caffeine or medication recommendations.
- Football, basketball, motorsport, baseball and esports viewing durations are editable calculation examples. Actual schedules and highlight or replay availability are not checked.
- Inputs are calculated in your browser and are not sent to analytics tools or a server. Hosting access logs are separate; this does not mean the entire site processes no information.
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Frequently asked questions
Is this measured sleep?
No. It is time available for sleep under manually entered dates and buffers. The tool does not measure sleep or fetch sports schedules.
Why subtract sleep-onset time?
An editable allowance is deducted once per available interval. Intervals shorter than that allowance contribute zero, not a promise of useful sleep.
Is split sleep equivalent to continuous sleep?
The planner makes no claim of equivalent recovery. It reports interval counts and the longest continuous interval rather than evaluating sleep quality or stages.
How are delays handled?
Edit the duration or explicit end date and time, or choose a 30/60-minute delay scenario. All dependent viewing options and share text use that same revised end.
Which date should a dawn broadcast use?
Use the explicit date in Asia/Seoul, UTC+09:00. A 04:00 broadcast after January 1 bedtime may be January 2. Automatic conversion from overseas local time is not supported.
What happens outside the sleep window?
Preparation and post-viewing buffers are checked too. A fully outside blocked interval leaves the skipping baseline unchanged; a fully covered window gives zero.
Why do viewing loss and target shortfall differ?
Loss compares with skipping under identical bedtime, wake time and sleep-onset assumptions. Shortfall compares with your chosen target, which may already exceed the skipping baseline.