Writing Price Decimals as Superscript A/B Test

Sessions that stall on the price area and then leave, survey comments about cost, or a heatmap where attention clusters on the price block suggest visitors find the price high. If superscript decimals help, the price feels lighter and visitors move to purchase more readily. If visitors leave because of taxes or extra fees, make the total clear first, and do not test a display that blends those decimals into the main amount. In markets that regulate price display, check the applicable rules before changing the format.

Purchase conversion rate (CR)

Compare purchases to see whether price formatting changes conversion.

Also track

• Average purchase valueRead completed-order value alongside conversion.
• Price comprehensionIf surveyed, ask the same brief question in both arms to check whether visitors can state the total payable amount.
• Price-related disputes and returnsTrack recorded disputes and returns related to an unexpectedly high price over the same follow-up period.
• Time to purchaseRead time alongside purchase rate; longer time is not automatically negative.

• FormatCompare superscript decimals with standard-size decimals.
• ReadabilityCheck that smaller decimals remain clear on mobile.
• Price rangeReview whether the effect differs for lower- and higher-priced items.
• Rounding perceptionUse the same method in both arms to ask whether visitors can identify the actual total.
• SegmentsDefine segments before display; do not infer price sensitivity from purchase behavior in the test.

1. 1A conversion gain alone is not enough; track price-related disputes and returns over a follow-up window of equal length and check average purchase value. If price comprehension drops or the decimals become hard to read, especially on mobile, the gain does not earn a launch, because the total payable must always stay readable.
2. 2Credit the result to the format only if the price level stayed the same; if prices changed too, the difference may not come from formatting. Apply the format consistently across comparable products during the test, and read the effect within predefined price bands.
3. 3Do not treat a longer time to purchase as negative on its own. When the conversion difference is small, check whether chance could explain it with the A/B test significance calculator, and if it stays unclear, report it as inconclusive rather than as a small win.