Discount or Point Rewards — Which Is the Better Deal?
＋More features: break-even reward rate, and points you never use
What reward rate matches an X% discount?
Works out the break-even point for “buy in the X%-off sale, or in the point-reward campaign?”
What if you will not use all the points?
Calculates your real saving when you will not use the points up — for example, “I will probably use only about 70%”.
“10% off” and “10% back in points” — they look the same, but the discount is actually the slightly better deal. This tool calculates the effective cost of both and tells you which wins. Point-reward campaigns are everywhere in Japanese shops and cashless apps; use this when you have to choose between a sale price and a point campaign.
How to use
- Enter the item price.
- Enter the discount rate and the point reward rate you want to compare (either can be 0).
- As soon as all three are filled in, the verdict and a comparison table appear — no button needed.
How it is calculated
- Discount: payment = price × (1 − discount rate ÷ 100)
- Point rewards: effective cost = price × (1 − reward rate ÷ 100) (assuming you later use all the points you earn)
- With point rewards, however, the amount you actually pay stays at full price. Points worth r yen per 100 yen convert to a discount rate of 100r ÷ (100 + r) % (10% back is 1000 ÷ 110 = about 9.09% off). This is why the discount wins at the same number.
- Example: for a 10,000-yen item, “10% off” means paying 9,000 yen. “10% back” means paying 10,000 yen and getting 1,000 points (effectively 9,000 yen), but converted to a discount that is only 9.09%, so 10% off is the better deal.
Sources and assumptions
- This is an arithmetic calculation. Points are assumed to be worth 1 yen each and fully usable later.
Assumptions and notes
- If the points expire, are limited in where you can spend them, or are easy to forget, their real value is lower than calculated.
- Many schemes give no points on the part you pay with points — another reason rewards are slightly worse than a discount.
- In campaigns with a reward cap (for example, up to 2,000 points), the effective reward rate drops for expensive items.
Frequently asked questions
Why are “10% off” and “10% back” not the same?
With 10% off you buy a 10,000-yen item for 9,000 yen. With 10% back you pay 10,000 yen and receive 1,000 yen in points — you bought 11,000 yen of value for 10,000 yen, which is about 9.09% as a discount. The discount, which reduces your payment up front, always wins slightly.
What reward rate matches “20% off”?
25% back. Putting r = 25 into the conversion formula 100r ÷ (100 + r) gives 2500 ÷ 125 = 20%, exactly equivalent to 20% off.
If I am going to use the points anyway, is it effectively the same?
If you reliably use every point, the effective cost is the same (9,000 yen either way for 10,000 yen at 10%). But rewards are still less favorable in that your money goes out first and points can expire or be forgotten. This tool shows both views: the effective cost and the discount-equivalent rate.