BRING THE DATES. KEEP THE CONTEXT.
What were the gaps between those dates?
When dates are scattered across notes, it is easy to lose track of the intervals. Put recorded starts in one place and see the calendar-day gaps clearly.
Try the free tool ↓Descriptive arithmetic only. No diagnosis, normal-range label, next-period forecast or fertility advice. No dates are submitted or saved by this page.
THE INTERACTIVE WORKSPACE
Compare the dates you actually recorded.
Bar widths compare only the intervals in this log. Color carries no medical meaning. The median is the middle interval after sorting; for an even number of intervals, it is the average of the middle two.
Before using this summary: check whether any starts were missed, estimated or entered incorrectly. A missing record can make a gap look longer. These calculations do not establish complete menstrual cycles or explain bleeding.
USE IT IN REAL LIFE
A number is more useful with a note beside it.
For the fictional dates June 1 and June 29, the gap is 28 calendar days. Counting both endpoints as separate days would give the wrong interval. This tool subtracts date-only calendar values, so a daylight-saving clock change does not add or remove a day.
- Check the source. Distinguish a date written down at the time from one remembered later.
- Keep gaps in the record visible. An absent note is unknown, not proof that nothing happened.
- Keep your own context. If you want to discuss a change at an appointment, bring the original dates, relevant notes and your question. The summary does not replace them.
This page cannot determine perimenopause, menopause, pregnancy, causes of bleeding or whether a pattern needs treatment. Discuss medical concerns with a qualified healthcare professional; do not use this arithmetic to make medical or contraception decisions.
THE NEXT STEP
Remember what changed—not just the date.
My Midlife Story lets you record period notes alongside symptoms and other changes, find earlier entries, and choose notes for an editable appointment brief. Keep the original context available when you prepare your questions.
Get My Midlife Story’s free logging tools ↗Free includes logging, history, search, visit briefs and PDF export. Optional Premium adds deeper organization and comparisons through a paid auto-renewing subscription. Prices appear in the app. Requires iOS 18+. This browser calculator is separate and does not sync to the app.
Publisher disclosure: Honest Little Apps publishes My Midlife Story and this companion. This is not an independent review. App details checked November 4, 2026.
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