A 90-day habit tracker spreadsheet for Google Sheets and Excel. 12 habits, 90 day columns, live streak formulas, and a weekly review sheet. You mark x or m each day, the formulas count the streaks. No add-ons, no scripts, no subscriptions.

What you get (two CSVs + setup guide):

1. Habit Tracker (habits.csv) - 12 pre-named habits across Focus / Health / Mind / Work: deep work, workout, reading, no-phone morning, sleep before 11, water 2L, journaling, inbox zero, side project hour, stretch, walk 30 min, gratitude note. 90 day columns (D1-D90) per habit. Rename them or add your own rows.

2. Live streak formulas - the Streak column finds your last marked day: if it's an x it counts the current run back to your last miss, if it's an m it shows 0 so you know to restart. The "Done of 90" column counts every x in the row. Standard functions only (IF, SUMPRODUCT, MAX, COLUMN, COUNTIF), works in Google Sheets and Excel with no array entry.

3. Weekly Review (weekly-review.csv) - 8 week rows with pre-filled day ranges (Day 1-7 through Day 50-56, add rows to continue through Day 90) and three prompts: wins, misses, and one adjustment for next week.

Why a tracker with formulas instead of an app: no account, no notifications, no monthly fee. It's one sheet you fill for 13 weeks, and the streak numbers update as you type.

Setup takes 2 minutes: in Google Sheets, File → Import → Upload the CSVs. In Excel, open the CSVs directly. The first three rows ship with sample marks so you can see the streaks move, then clear them and start day 1.

Honest notes: this counts days, it doesn't remind you - no notifications or app sync. Formulas verified by Python logic re-check and syntax inspection, not by opening in Excel/LibreOffice.

License: personal and commercial use. No reselling the pack as-is or with minor changes.