Discount and Margin Calculator

📖 Tool Introduction

Promotions keep multiplying: a straight discount, a threshold coupon, a stacking coupon, and the price you actually pay rarely matches the advertised saving.

This calculator separates the three questions: turn a discount into a price, turn a price back into the real discount, and turn a cost into a margin or a price.

With a threshold coupon applied it reports the effective discount, so claims like fifteen percent off then fifty more cannot mislead you.

Every figure you type stays inside this browser tab. The arithmetic runs as plain JavaScript on your own device, so nothing is uploaded to a server, nothing survives after you close the page, and there is no account to create or sign in to. You can enter real numbers without worrying about them leaving your machine.

What comes out is a mathematical projection built on the assumptions you supply, and the assumptions are the part worth checking. Real outcomes turn on details no calculator can see: the exact wording of a loan contract, the policy in force in your city this year, the way your own body responds. Use these numbers to orient yourself and to compare one option against another, then confirm anything that carries real consequences against an official document or a professional who can look at your actual circumstances rather than a generic formula. Where a result feeds into a decision that costs money or affects your health, treat it as the opening of a conversation with someone who can see the whole picture rather than as the answer in itself.

The inputs here are deliberately plain: no file to upload, no network call, no queue to wait in. That keeps the tool fast and private, and it also means no record exists anywhere of what you calculated, so nothing you try here can come back to you later.

✨ Key Features

• Discount to price, including the effective price after a threshold coupon
• Price to discount, to expose inflated originals
• Cost-plus pricing: target a margin and derive the selling price
• Both gross margin and markup, which are measured differently
• Batch comparison of common discount tiers and savings
• Recalculates the moment you change any figure, with no waiting and no separate submit step

🚀 How to Use

1. Choose a mode: discount to price, price to discount, or margin
2. For discount to price enter the original price and the discount, where eighty-five means fifteen percent off, plus any coupon
3. To reverse, enter the original and the current price
4. For margin enter selling price and cost, with an optional quantity for total profit
5. The result panel shows the discounted price, the saving and the effective discount

⚠️ Things to Note

• How to enter the discount: A value of 85 means eighty-five percent of the original price, not a reduction of eighty-five. Take care when entering it
• Margin versus markup: Gross margin is profit over selling price while markup is profit over cost. The same twenty yuan of profit gives different figures
• Shipping and fees excluded: This tool ignores shipping, tax and platform commission, so actual net profit will be lower
• Computed locally in your browser: Every figure is worked out inside your own browser and nothing is sent to a server. The values disappear when you close the page, so you can safely enter real numbers
• Indicative results only: What you see here is a mathematical projection. For contracts, tax filings or medical decisions, rely on the official documents issued by the relevant authority rather than on this tool