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Inside the Ecommerce Forecasting Tool

Sheet-by-sheet reference: every input, formula, and output. Use this to scan the model before purchase, or as a cell-level reference when editing with AI.

9 sheets4 sections

How to read this

Cells are referenced by R<row>/<column><row> notation. R9/E9 means column E, row 9. R38–R45 is a block of inputs spanning those rows. Multi-column ranges like D39–J39 mean the same row across several columns. Types: INPUT = user-edited, FORMULA = calculated, DROPDOWN = select from list.

Ecommerce Forecasting Tool — Sheet Map

Sheets (9)

README, License, Disclaimer, Get Started, Key Reports, Forecast, Historicals, Model Comparison, Changelog

Get Started (B1:F49)

Setup (R5-R14)

Row Label Type Default
R6/D6 Company Name INPUT "Company"
R7/D7 Currency INPUT "$"
R8/D8 First forecast date INPUT (date) Jan 2025
R9/D9 Fiscal year end INPUT (date) Dec 2025
R12/D12 First historical date INPUT (date) Jan 2021
R13/D13 Historical FY end INPUT (date) Dec 2021
R14/D14 Last historical date INPUT (date) Dec 2024

Revenue & Marketing (R16-R34)

Row Label Type Default
R17/D17 Avg Revenue per Order, new INPUT ($) $50
R18/D18 Avg Revenue per Order, repeat INPUT ($) $40
R19/D19 Baseline rate of change AOV INPUT (%) 10%
R20/D20 Rate decline per month INPUT (%) -5%
R22/D22 Cost of Sales % INPUT (%) 25%
R23/D23 Additional COGS % INPUT (%) 10%
R24/D24 Additional COGS % (2nd) INPUT (%) 0%
R28/D28 Shipping Revenue per order INPUT ($) $0
R29/D29 Shipping Cost per order INPUT ($) $0
R31/D31 CAC new customer INPUT ($) $30
R32/D32 CAC repeat customer INPUT ($) $10

Growth & Churn (R36-R48)

Row Label Type Default
R37/D37 Date to start growth INPUT (date) Jan 2025
R38/D38 New Customers first month INPUT (#) 550
R39/D39 Baseline growth rate INPUT (%) 90%
R40/D40 Growth rate decline per month INPUT (%) -15%
R41/D41 Conversion rate (sessions→orders) INPUT (%) 2%
R42/D42 Customers beginning INPUT (#) 0
R43/D43 Churn rate per period INPUT (%) 50%
R44/D44 Repeat cycle months INPUT (#) 3
R47/D47 After N total customers adjust INPUT (#) 0
R48/D48 Change cohort performance by INPUT (#) 1

Forecast (B1:BO199) — Cohort-based

Assumptions (R15-R48): Mirrors Get Started — FORMULA

Retention Curve (R44):

  • Calculated from churn rate and repeat cycle
  • Can be overwritten with manual retention curve
  • R46: Adjustment factor applied to all cohorts

Orders (R50-R100+):

  • R51: Website Traffic (FORMULA from orders ÷ conversion)
  • R52: New Customers per period (FORMULA)
  • R54: Total Orders (FORMULA: sum of all cohorts)
  • R55-R100+: Individual monthly cohorts — each row is a cohort, columns track orders per period (FORMULA based on retention curve)

Revenue (R103+):

  • Orders × AOV per cohort
  • Separated into new vs repeat revenue
  • COGS, shipping, marketing spend calculated

Unit Economics (R150+):

  • CAC, LTV, payback period
  • Contribution margin

Historicals (B1:BO66) — Optional INPUT

  • Monthly cohort data for historical performance
  • Users enter actual order counts per cohort
  • Model blends historical retention with forecast assumptions

Key difference

Cohort-based, not subscription. Each monthly cohort tracked separately. Retention = repeat purchase probability, not subscription churn.

Ready to put this to work?

View the Ecommerce Forecasting Tool