Discount math · coupon decisions

When Does a Dollar-Off Coupon Beat Percent Off? The Break-Even

"$10 off" sounds smaller than "20% off." Sometimes it is; sometimes it saves you twice as much. The whole contest comes down to one number — the break-even price — and you can compute it in your head.

The break-even point

The two coupons are equal when the dollar amount is exactly the given percent of the price:

break-even price = dollar amount ÷ percent

For $10 off vs 20% off: $10 ÷ 0.20 = $50. At exactly $50, both coupons take $10 off. Below $50, the fixed $10 is a bigger slice — the dollar coupon wins ($10 off a $40 item beats 20%, $8 vs $10). Above $50, the percent scales past it — 20% off $80 is $16, beating $10.

The intuition: a dollar-off coupon is worth the same at every price, while a percent-off coupon grows with the price. Cheap items favor the dollar coupon; expensive items favor the percent.

Common break-evens at a glance

Read: with a $5-off coupon against 25% off, the dollar coupon wins below $20.

The fine print changes the answer

The arithmetic picks a winner; the coupon terms can overrule it:

• Minimum spend. Many dollar-off coupons require a minimum purchase — a $10-off-$50 code isn't usable below $50 at all, which flips cheap-item cases entirely.
• Category exclusions. Percent-off coupons often exclude brands or clearance; dollar-off rewards sometimes apply storewide. Check which coupon actually covers your item before comparing values.
• One per order. If you can only use one, this comparison decides; if a store allows both types together, the percent typically applies first and the dollar coupon after — the two-discounts-in-a-row math covers that case.

Retailer-level stacking structures — which coupon types combine, in what order — are in the manufacturer vs store coupon guide and the coupons-per-order table.

Try your two coupons

The card above computes the break-even for your exact pair and shows which coupon wins at your price. For any deeper stacking — three coupons, tiered percent codes — the stacked discount calculator handles the full chain.

This page is arithmetic plus general coupon-rule patterns, not advice. Your coupons' own terms — minimums, exclusions, per-order limits — govern what actually applies at checkout.