How to Build Your Own Cycle Syncing Template

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If you like to see how things work before you hand them to an app, a template is a great way to start cycle syncing. In about ten minutes you can build a sheet that tells you your cycle day and phase for any date, and plan your week around it.

Below is a template you can build yourself, with formulas you can copy. At the end we’ll be honest about where a template stops working and an app takes over. (New to the phases? Read what cycle syncing is first.)

How the Template Works

The template needs three numbers from you:

The first day of your last period.
Your average cycle length, for example 28 days.
Your average period length, for example 5 days.

From those, it works out the phase of every date using a common approach: the luteal phase is counted as the last 14 days of your cycle, the ovulatory phase as the 4 days before it, your period as the first days, and the follicular phase as everything in between. For a 28-day cycle with a 5-day period that gives:

Menstrual: days 1–5
Follicular: days 6–10
Ovulatory: days 11–14
Luteal: days 15–28

These are estimates. Real cycles vary, and ovulation doesn’t always land on the same day, so treat the phases as a planning guide, not a medical prediction.

Build It in Google Sheets or Excel

Open a new sheet and type these labels and your own numbers:
- In A1 type Last period start, and in B1 the date (for example 10/1/2026)
- In A2 type Cycle length, and in B2 your number, like 28
- In A3 type Period length, and in B3 your number, like 5
In A5, B5 and C5, type the headings Date, Cycle day and Phase.
In A6, type today’s date. In A7, type =A6+1 and drag it down for as many days as you want to plan.
In B6, paste this formula and drag it down. It works out the cycle day for each date:
```
=MOD(A6-$B$1,$B$2)+1
```

In C6, paste this one and drag it down. It turns the cycle day into a phase:

=IFS(B6<=$B$3,"Menstrual",B6<=$B$2-18,"Follicular",B6<=$B$2-14,"Ovulatory",TRUE,"Luteal")

Add columns after Phase for what you want to plan: Workout, Food, Work, Rest, Social.
Optional: colour each phase with Format → Conditional formatting (in Excel, Home → Conditional Formatting), using “Text contains Menstrual” and so on.

IFS works in Google Sheets and in Excel 2019 or later. In an older Excel, nest IF formulas instead.

Build It in Notion

Create a database with a Date property.
Add a Formula property called Cycle day, with your last period date and cycle length written into it:
```
mod(dateBetween(prop("Date"), parseDate("2026-10-01"), "days"), 28) + 1
```

Add a second formula called Phase, using the same thresholds as the sheet (5 for your period, 28 for your cycle):

ifs(prop("Cycle day") <= 5, "Menstrual", prop("Cycle day") <= 10, "Follicular", prop("Cycle day") <= 14, "Ovulatory", "Luteal")

Switch the database to a calendar view, and add your plans as entries. (These formulas are for dates after your last period starts.)

What to Put in Each Phase

Start small: one or two things per phase, then adjust as you learn your own pattern.

Menstrual: lighter plans, rest, warm meals, gentle movement. See the menstrual phase guide.
Follicular: new projects, learning, building up workouts. See the follicular phase guide.
Ovulatory: meetings, presentations, social plans, harder workouts. See the ovulatory phase guide.
Luteal: finishing and tidying up, steadier workouts, getting ready for your period. See the luteal phase guide.

Where a Template Stops Working

A template is a great start, but you’ll probably hit these walls within a few months:

Your cycle changes, the sheet doesn’t. When a period comes early or late, every date after it is wrong until you update the start date by hand.
It’s not in your calendar. You still check the sheet and your calendar separately.
Routines don’t repeat by phase. Your “yoga in the luteal phase” doesn’t move when your luteal phase does.
No reminders. Nothing tells you your period is a few days away.

That’s what Kilova does for you. It recalculates your phases each time you log a period, shows them in your calendar (and in Google Calendar, Outlook or Apple Calendar if you connect one), and Phase repeat keeps routines in the right phase every cycle. If you’d rather not fill in the columns yourself, Your Routine builds a plan for each phase from a few quick questions. Kilova is on iPhone, Android and the web; calendar sync and routines are part of Premium, with 2 months free for new accounts.

Comparing tools? See period trackers that sync with your calendar and how to build a cycle syncing planner.

Frequently Asked Questions

Is the template accurate? It’s as accurate as your averages. It assumes every cycle is the same length, which they rarely are, so update the start date each time your period begins.

What if my cycles are irregular? A fixed-length template will drift a lot. Update it with every period, or use an app that recalculates for you.

Does cycle syncing work on hormonal birth control? Most hormonal contraception stops ovulation, so the four natural phases don’t happen in the same way. Many people still track how they feel through the month and plan around that.