How The Calculator Works

MaddyCoupons provides a free, instant coupon savings calculator that works entirely in your browser — no signup, no data collection, no server calls.

Three Coupon Modes

Percentage Off — Enter your discount percentage (e.g. 25%) and we calculate exactly how much you save on the full order, including multi-quantity purchases.

Fixed Dollar Off — Got a "$15 off" coupon? Enter the amount and we'll show your final cost with tax included.

Buy X Get Y Free — BOGO deals are deceptively tricky. A "Buy 2 Get 1 Free" is actually only 33.3% off, not 50%. Our calculator does the group math for any quantity so you know the real effective discount rate.

Tax Calculation

Enter your local sales tax rate and we'll apply it to the discounted subtotal — giving you the true final checkout price with zero surprises.