Discount Calculator

Calculate discount amounts, stacked discounts, tax, and total savings instantly.

100% Free No Sign-Up Calculated in Your Browser

Original Price ($)

Discount Type

Discount (%)

Additional/Stacked Discount (%) optional

Applied after first discount (e.g., clearance + coupon)

Sales Tax Rate (%)

Final Price (after tax)

—

Including all discounts + tax

Discount Amount

—

First discount

Price After Discount

—

Before tax

Stacked Discount

—

Additional savings

Price After Stack

—

Before tax

Tax Amount

—

Effective Discount %

—

Combined savings

—

Total Savings: —

Calculate the final price after one or two stacked discounts plus sales tax, and see your total percentage savings.

How It Works

How Discount Calculator Works

A percentage discount is calculated as Discount Amount = Original Price × Discount % ÷ 100, and the price after discount is simply the original price minus that amount. If you enter a second, stacked discount (like a clearance markdown plus a coupon), it is applied to the already-discounted price, not the original price — which is why two 20% discounts stacked together save less than 40% overall.

Sales tax is applied last, calculated on the final discounted price rather than the original price, which reflects how most retailers actually calculate tax at checkout.

The effective discount percentage shown at the end reflects your true total savings relative to the original price, combining both discounts (but excluding tax, since tax is a separate cost rather than a savings).

Worked Example

See It In Action

A $100 item with a 20% discount drops to $80.00 before tax (saving $20). Adding 8% sales tax on that $80 discounted price adds $6.40, bringing the final price to $86.40 — still 13.6% less than the $100 original price, even after tax.

Real-World Use Cases

Who Uses Discount Calculator and Why

Calculating the final price of an item after a single percentage-off sale, including sales tax.
Working out the true combined savings from a store discount stacked with a coupon.
Converting a flat dollar-off discount into its equivalent percentage savings.
Checking whether a "40% off" claim on two stacked 20% discounts is actually accurate before assuming the total savings.

Common Mistakes

Mistakes to Avoid

Assuming two stacked 20% discounts add up to 40% off — they don\'t, because the second discount applies to the already-reduced price, not the original; two 20% discounts stack to a combined 36% off, not 40%.
Calculating sales tax on the original price instead of the discounted price — most retailers apply tax after discounts, on the final discounted price, which is what this calculator does.
Including tax in the "effective discount percentage" figure — that figure reflects only your savings relative to the original price before tax, since tax is a separate added cost rather than a form of savings.

Pro Tips

Tips for Best Results

When comparing two stacked discounts against a single equivalent discount, calculate the stacked result first — it will always be a smaller combined percentage than simply adding the two individual percentages together.
If a store advertises a flat dollar amount off instead of a percentage, switch the discount type to "Amount ($)" to still see the equivalent percentage saved for comparison against other deals.

Troubleshooting

Fixing Common Problems

My total discount seems smaller than expected after stacking two percentages. — This is expected behavior, not an error — sequential percentage discounts compound against a shrinking price, so their combined effect is always less than simply adding the two percentages together.

Glossary

Terms Explained

Stacked discount: A second discount applied on top of an already-discounted price, rather than to the original price.

Effective discount percentage: Your true total savings relative to the original price, combining all discounts applied but excluding any tax.

FAQ

Frequently Asked Questions

Why don't two stacked 20% discounts equal 40% off?

Because the second discount applies to the already-reduced price, not the original price. Two 20% discounts stack to a combined 36% off ($100 → $80 → $64), not 40% off.

Is sales tax calculated before or after the discount?

This calculator applies tax after all discounts, on the final discounted price — which matches how most US retailers calculate tax at the register.

Can I enter a flat dollar discount instead of a percentage?

Yes — toggle the discount type to "Amount ($)" to enter a fixed dollar discount instead of a percentage, and the calculator will still compute the equivalent effective percentage saved.

What does "effective discount %" mean?

It's your total savings (across both discounts, before tax) expressed as a single percentage of the original price — useful for comparing deals that use different discount structures.