Spaced Review Calendar

How to use this calculator

Enter planning dates, review weekdays, a daily time cap and offsets such as 1, 3, 7 and 14 days. Add each item's learning date and minutes needed per review.

Offsets always refer to the learning date. Earlier due reviews receive capacity first; equal due dates follow item order. Sessions are not split. Reviews of one item stay on separate dates. Delays do not shift the original due dates of later reviews.

A worked example

An item learned November 2, 2026 with offsets 1, 3 and 7 is due November 3, 5 and 9. If November 5 is unavailable, that session moves to the next eligible date with space, while November 9 remains the next original due date.

Is this an adaptive memory algorithm?

No. It is an inspectable fixed-offset planning calendar. It does not estimate retention, grade recall or reproduce Anki's scheduling algorithm. Deferred and unallocated sessions are shown explicitly.

Further reading: Source workflow and conventions. Your entered rules determine this result.

Which calendar and years are supported?

Use Gregorian dates from 1900 through 2100, with results inside that range. Most daily plans are limited to 366 dates; academic terms and sprint plans allow up to 731. Forms limit the number of entries to keep calculations responsive. Holidays and policy rules come from your inputs. Date-only plans ignore DST; tools with time-zone inputs use the browser's time-zone data and explicitly resolve repeated times. Calendar exports preserve date-only markers or exact timed events as appropriate. Calculations run only when requested, without background polling.

What happens to my dates?

Calculations run on your device. Saving a calculation is optional and keeps it in this browser. A setup link contains the dates and settings you entered; anyone with the link can read them. Use one tab per saved calculator. Clear saved data from Privacy & settings.