Inputs
Enter control and coupon performance
Tip: Use visitors and orders from the same timeframe and traffic source.
Example
Sample input dataset
| Group | Visitors | Orders | AOV | Gross margin | Discount / order |
|---|---|---|---|---|---|
| Control | 10,000 | 320 | $55.00 | 45% | $0.00 |
| Coupon | 9,500 | 380 | $55.00 | 45% | $5.00 |
Replace these values with your A/B test or campaign totals.
Formulas
What this calculator computes
- Conversion rate: CR = Orders / Visitors
- Absolute lift: Lift(pp) = (CR_coupon − CR_control) × 100
- Relative lift: Lift(%) = (CR_coupon − CR_control) / CR_control × 100
- Incremental orders: ΔOrders = Orders_coupon − (CR_control × Visitors_coupon)
- Incremental revenue: ΔRev = ΔOrders × AOV
- Incremental gross profit: ΔGP = ΔRev × GrossMargin
- Discount cost: DiscCost = max(0, ΔOrders) × DiscountPerOrder
- Net profit: Net = ΔGP − DiscCost − FixedCost
- Significance (two-proportion z-test): pooled standard error, then two‑tailed p‑value.
- 95% CI: unpooled standard error for (CR_coupon − CR_control).
How to use
Practical steps for accurate lift estimates
- Pull visitors and orders for a control group without coupons.
- Pull visitors and orders for the coupon-exposed group.
- Enter AOV and gross margin to estimate profit impact.
- Enter average discount cost per incremental order.
- Add fixed campaign costs if you paid for placement or tools.
- Click Calculate Lift, then download CSV or PDF for reporting.
Why conversion lift matters for coupons
Coupons often increase orders, but they can also shift demand from shoppers who would have purchased anyway. This calculator separates genuine lift from normal baseline performance by comparing a coupon group with a control group. Using visitors and orders, it outputs conversion rates, lift in percentage points, and incremental orders that can be attributed to the offer.
Inputs that drive reliable lift
Accurate lift starts with clean group totals. Use the same date range, channel mix, and attribution model for both groups. Large samples reduce noise: 5,000–20,000 visitors per group yields tighter confidence intervals. Remove obvious bot traffic and ensure the coupon group reflects actual eligibility rules. Enter AOV to translate incremental orders into revenue, and add gross margin to estimate profit impact.
Interpreting absolute vs relative lift
Absolute lift answers “how many points did conversion move,” for example from 3.2% to 4.0% equals +0.8 pp. Relative lift expresses that change versus baseline, here +25%. Absolute lift is better for forecasting volume; relative lift is helpful when comparing categories with different baselines. If the control rate is very low, focus on absolute lift and confidence intervals to avoid exaggerated percentages.
From lift to incremental profit
Incremental orders are computed as coupon orders minus the control conversion rate applied to coupon visitors. Revenue impact equals incremental orders × AOV. Gross profit uses revenue × margin, then subtracts coupon costs. Discount cost is modeled per incremental order, so you can estimate whether the extra volume pays for the incentive and any fixed campaign fees. A quick check is “breakeven discount”: AOV × margin indicates the maximum discount per incremental order before profit turns negative.
Decision thresholds and reporting
Statistical results help avoid overreacting to random spikes. The two‑proportion z‑test returns a p‑value, while the 95% confidence interval shows a plausible range for lift. Many teams treat p ≤ 0.05 as strong evidence, but business thresholds matter too: require net profit > 0 and incremental orders within capacity. Segment results by device, new versus returning shoppers, or traffic source. Export CSV or PDF to share the lift summary, profit impact, and significance in weekly performance reviews.
FAQs
1) What is “conversion lift” in this calculator?
Conversion lift is the difference between coupon conversion rate and control conversion rate. It is shown as percentage points and as relative percent change versus the control baseline.
2) Do I need an A/B test to use it?
No. You can use any comparable control versus coupon split (holdout, geo test, or audience split). The key is consistent tracking for both groups in the same timeframe.
3) Why can incremental orders be negative?
If the coupon group converts worse than the control baseline, incremental orders will be negative. That indicates the offer did not improve conversion for that audience or period.
4) How is discount cost calculated?
The calculator multiplies the average discount per order by incremental orders (only when incremental orders are positive). This estimates incentive cost tied to the extra volume created.
5) What does the p-value mean here?
The p-value comes from a two-proportion z-test comparing conversion rates. Smaller values suggest the observed lift is less likely to be random variation, given the sample sizes.
6) How should I interpret the 95% confidence interval?
The interval is a plausible range for true lift in percentage points. If it crosses 0.0 pp, the data does not strongly rule out no lift at the 95% level.