Choose a metric because it supports a decision
Ecommerce metrics describe your store’s activity and performance. A key performance indicator, or KPI, is a metric you choose to judge progress toward a specific goal. A store trying to improve checkout needs different evidence from one evaluating the cost of acquiring new customers.
Start with a question, define the calculation and decide what you will review if it changes. A longer dashboard is not necessarily a better one. Revenue, order value and attributed advertising sales can rise while contribution falls.
This guide uses ten explicit definitions so you can compare the right inputs. All worked figures are fictional examples, not benchmarks, forecasts or Memberply customer results.
Download the free ecommerce KPI worksheet
Download KPI worksheet (.xlsx)
No email signup required. Open the workbook in spreadsheet software or import it into Google Sheets. It contains four tabs: Start here, Your worksheet, Example and Definitions. There are no macros or live account connections.
- Enter your own verified figures in the blue cells. Calculated results appear in the shaded result column.
- Record dates, currency, channel, filters and data sources alongside each metric. Cohort windows may differ from a monthly reporting period.
- Leave missing inputs blank. Zero means a verified zero, not information you could not find.
- For the CLV margin input, enter a decimal such as 0.40 for 40%. Result percentages are formatted automatically.
The worksheet keeps required-input results blank until numbers are supplied and flags invalid denominators or impossible subset counts. These checks cannot determine whether your underlying data or business assumptions are correct.
Ten ecommerce metrics, formulas and examples
1. Average order value (AOV)
Formula: Product revenue at order placement after discounts ÷ corresponding orders
Illustrative example: $12,000 ÷ 200 = $60
Compare basket value while also checking conversion and contribution. Shopify’s AOV excludes post-order adjustments; it is not total sales including tax and shipping. See the Shopify AOV definition. Use our AOV calculator and AOV strategy guide.
2. Online store conversion rate
Formula: Sessions with a purchase ÷ online store sessions × 100
Illustrative example: 180 ÷ 6,000 × 100 = 3%
Use session counts from the same source, channel and filters. Orders are not interchangeable with purchasing sessions because a session can contain multiple orders. Shopify describes this in its behavior reports. Break changes down by device and traffic source before blaming the checkout.
3. 90-day second-purchase rate
Formula: First-time buyers who make a second valid order within 90 days ÷ first-time buyers with a full 90-day observation window × 100
Illustrative example: 60 ÷ 200 × 100 = 30%
This is the worksheet’s specific cohort definition, not a universal definition of repeat purchase rate. Use customer-level order history and consistent rules for cancelled, test and returned orders. Do not compare a recent cohort with only 20 days of observation to one with the full window. The retention examples guide can help plan a relevant follow-up.
4. Blended customer acquisition cost (CAC)
Formula: Defined acquisition costs ÷ new customers acquired in the matching period
Illustrative example: $3,000 ÷ 100 = $30
List the costs included, such as ads, creative or agency fees, and be consistent. Returning customers do not belong in the new-customer denominator. Spending and acquisition can occur in different periods, so this simple period ratio needs context. Use the CAC calculator to examine your inputs.
5. Attributed return on ad spend (ROAS)
Formula: Attributed revenue ÷ advertising spend under one model and window
Illustrative example: $9,000 ÷ $3,000 = 3.0×
Record the attribution window and revenue treatment. Do not add overlapping attributed sales from several advertising platforms. ROAS is not profit or proof of incremental sales. The break-even ROAS calculator helps relate advertising revenue to a stated contribution assumption.
6. Contribution per order
Formula: Contribution after defined variable costs, before acquisition ÷ corresponding orders
Illustrative example: $5,000 ÷ 200 = $25
Build contribution from a consistent revenue basis and subtract the costs you define: for example product cost, fulfilment, payment fees and shipping subsidy. Include shipping collected if carrier costs are included. Account for returns consistently. This planning subtotal is before acquisition, fixed overhead and tax; it is not net profit.
7. Contribution margin
Formula: The same contribution amount ÷ the same revenue basis × 100
Illustrative example: $5,000 ÷ $12,000 × 100 = 41.7%
Do not divide product-only contribution by revenue that suddenly includes unrelated fees or taxes. Document what is in both amounts. A negative margin is possible and should not be hidden. For an offer decision, examine the discount profit calculator with its stated exclusions.
8. Revenue customer lifetime value estimate
Formula: Assumed AOV × orders per customer per year × assumed lifespan in years
Illustrative example: $60 × 4 × 3 = $720
This is a simple planning model with constant assumptions. It is not an observed lifetime result or a prediction for an individual customer. Keep time units aligned and test more than one plausible lifespan. Use the customer lifetime value calculator for scenarios.
9. Contribution customer lifetime value estimate
Formula: Revenue CLV estimate × assumed contribution margin
Illustrative example: $720 × 40% = $288
This is before acquisition and fixed overhead. With an illustrative $30 CAC, contribution after acquisition would be $258 under those assumptions. Subtract acquisition once, and include ongoing benefit costs either in the margin or separately, not twice. Do not compare revenue CLV directly with contribution CLV as if they were the same measure.
10. Starting-member retention
Formula: Members from the original active group still active at period end ÷ active members at period start × 100
Illustrative example: 90 ÷ 100 × 100 = 90%
Follow the original starting group directly. Exclude new members and reactivations from outside that group. Define what active means and use one period. This is different from repeat purchasing: an active member might not order that month. Our member retention calculator explains related scenarios.
Find the inputs and record their scope
On small screens, scroll the table horizontally.
| Question | Where to start | What to record |
|---|---|---|
| What did each order contain? | Shopify sales reports and order records | Revenue definition, order status, date range and currency |
| Which visits led to purchases? | One consistent session-based analytics report | Channel, bot filters, tracking changes and purchasing sessions |
| Who purchased again? | Customer order history or a cohort report | Customer identity, first-order window and observation length |
| What did acquisition cost? | Advertising and acquisition cost records | Included costs, timing, attribution model and new customers |
| What did each order contribute? | Revenue plus product, fulfilment, shipping and payment cost records | Actual variable costs and handling of refunds |
| Which members stayed active? | Verified membership status for the original starting group | Start/end dates, active definition and excluded new members |
Shopify’s customer reports distinguish new and returning buyers and offer cohort analysis. Check the report definition before assuming its repeat-purchase percentage matches this worksheet’s fixed 90-day second-order measure.
Account for measurement changes
Shopify documents a session-measurement rollout from September 21 to 23, 2026. It can change session counts and conversion rates even when sales and orders are unchanged. Review Shopify’s measurement-change guidance, use consistent filters and establish an appropriate new baseline before interpreting a shift as a store improvement.
Do not combine Shopify order totals with a different platform’s sessions and call the result Shopify’s reported conversion rate. Differences in identity, consent, time zones, attribution and exclusions can make tools disagree.
Turn the numbers into a focused review routine
- Choose one business question. For example, “Does the new shipping threshold improve contribution without reducing conversion?”
- Select a primary KPI and guardrails. Contribution might be primary, with AOV, conversion and returns used to interpret it.
- Record comparable inputs. Keep date windows, currency and audience consistent. Separate wholesale, retail and membership-fee orders if they behave differently.
- Investigate the change. Check tracking, stock, promotions and traffic mix before attributing it to your latest change.
- Choose one action and an owner. Record what you will test and when you will review it. Allow enough time for the buying cycle and relevant returns.
Illustrative warning: 200 orders at $60 produce $12,000. After a change, 160 orders at $70 produce $11,200 from the same amount of comparable traffic. AOV improved but revenue fell. The cost inputs are still needed to assess contribution.
Review operational issues as they arise, compare financial inputs over a consistent reporting period and revisit customer cohorts only when their observation window is mature. There is no universal good KPI target or test duration for every store.
Measure membership benefits without confusing activity with results
Memberply provides membership tiers and benefits. This worksheet is an educational resource, not an analytics dashboard connected to your shop.
When evaluating a program, keep membership-fee revenue, merchandise sales, member retention and benefit costs visible separately. A benefit claim is not necessarily a completed order, and an email click is not a verified redemption. Use actual records for the outcome you report.
Members may have been stronger customers before joining. Comparing members with all non-members does not establish that the program caused their spending. Where practical, use a credible comparison and account for customer selection, timing and reward costs. Our loyalty program strategy guide and loyalty ROI calculator help structure those questions.
Ecommerce KPI questions
What are ecommerce metrics and KPIs?
Ecommerce metrics describe store activity or performance. A KPI is a metric chosen to judge progress toward a specific objective. For example, conversion rate can support a checkout-improvement goal, while contribution per order checks whether extra revenue covers variable costs.
Which ecommerce KPIs should a small store start with?
Start with a small set that answers your current questions: conversion rate, average order value, contribution per order, acquisition cost and a clearly defined repeat-purchase measure. Add other metrics only when they support a decision and you have reliable inputs.
Is the KPI worksheet free to download?
Yes. The XLSX workbook is available without an email signup. It includes a blank worksheet, fictional worked examples, definitions and instructions. It has no macros or live account connections.
Why does the worksheet show a blank result or Check inputs?
A blank result means required numeric inputs are missing. Check inputs appears for invalid values such as a zero denominator or a retained-member count larger than the starting group. Missing information should not be entered as zero.
Is repeat purchase rate the same as member retention?
No. The worksheet’s 90-day second-purchase rate tracks another order within a fixed window after the first purchase. Starting-member retention tracks which members from an original active group are still active at the end. A member can stay active without ordering during that period.
Is ROAS a measure of profit?
No. ROAS divides attributed revenue by advertising spend under a chosen attribution model and window. It does not deduct product, fulfilment or other costs, and it does not prove that the advertising caused every attributed sale.
Does the CLV worksheet predict customer lifetime value?
No. Its simple revenue CLV estimate multiplies assumed order value, orders per year and lifespan in years. Contribution CLV applies an assumed contribution margin before acquisition and fixed overhead. These are planning scenarios, not forecasts or observed lifetime results.
Can the worksheet connect to Shopify or Memberply?
No. Enter verified aggregate figures from your reports manually. The worksheet does not access accounts, upload customer information or replace Shopify reporting. Memberply’s membership benefits are separate from this educational resource.