How to Calculate Profit Percentage and Loss Percentage (With Formula & Examples)

Whether you’re a student solving exam problems, a shopkeeper pricing goods, or an online seller checking margins on a spreadsheet, profit percentage and loss percentage tell you the same thing: how much you gained or lost compared to what you originally spent. Get this number wrong and every pricing decision built on top of it is wrong too.

This guide walks through both formulas step by step, shows how they apply in real shopkeeper, student, small business, and e-commerce situations, and clears up the mix-ups people run into most — like confusing profit percentage with profit margin, or accidentally calculating the percentage on the selling price instead of the cost price.

If you’d rather skip the manual math, our Profit & Loss Calculator does this instantly — enter your cost and selling price and it returns your exact profit or loss percentage.

What Is Profit Percentage?

Profit percentage is the profit you made on a transaction, expressed as a percentage of what you originally paid (the cost price). It answers a simple question: “For every 100 rupees I spent, how much did I gain?”

Profit happens when the selling price (SP) is higher than the cost price (CP). The rupee amount of profit only tells half the story — ₹500 profit sounds great until you learn it took a ₹50,000 investment to earn it. That’s just a 1% return. Profit percentage puts every transaction, big or small, on the same scale so you can actually compare them.

What Is Loss Percentage?

Loss percentage works the same way but in reverse. It’s the loss expressed as a percentage of the cost price, and it applies whenever the selling price is lower than what you paid to acquire or make the item.

Knowing your loss percentage matters just as much as knowing your profit percentage — it tells you exactly how much value slipped away relative to your investment, which is essential for deciding whether to hold, discount further, or write off stock entirely.

Profit Percentage Formula

The standard formula is:

Profit % = (Profit ÷ Cost Price) × 100

Where Profit = Selling Price − Cost Price (only when SP is greater than CP).

Loss Percentage Formula

The loss formula mirrors it exactly:

Loss % = (Loss ÷ Cost Price) × 100

Where Loss = Cost Price − Selling Price (only when CP is greater than SP).

Both percentages are always calculated against the cost price, never the selling price. This one detail is where most calculation errors happen, and we’ll cover it in more depth in the mistakes section below.

How to Calculate Profit Percentage (Step-by-Step)

1. Step 1: Write down your cost price and selling price.
2. Step 2: Confirm SP is greater than CP — if it isn’t, you’re dealing with a loss, not a profit.
3. Step 3: Subtract: Profit = SP − CP.
4. Step 4: Divide the profit by the cost price.
5. Step 5: Multiply by 100 to convert it into a percentage.

Worked example: CP = ₹200, SP = ₹250.

Profit = 250 − 200 = ₹50
Profit % = (50 ÷ 200) × 100 = 25%

For quick checks on the road or in-store, you can also plug these numbers into our Percentage Calculator once you’ve worked out the raw profit amount.

How to Calculate Loss Percentage (Step-by-Step)

1. Step 1: Write down your cost price and selling price.
2. Step 2: Confirm CP is greater than SP — otherwise you have a profit, not a loss.
3. Step 3: Subtract: Loss = CP − SP.
4. Step 4: Divide the loss by the cost price.
5. Step 5: Multiply by 100.

Worked example: CP = ₹500, SP = ₹400.

Loss = 500 − 400 = ₹100
Loss % = (100 ÷ 500) × 100 = 20%

Difference Between Profit Percentage and Profit Margin

These two terms get mixed up constantly, and the confusion has real financial consequences because they use different bases.

Take the same ₹200 CP and ₹250 SP example. Profit percentage comes out to 25%, but profit margin — profit divided by revenue — is (50 ÷ 250) × 100 = 20%. Same transaction, two different numbers, because the denominator changed. When you’re comparing your numbers against a business report or investor document, always check which base they’re using before drawing conclusions.

Difference Between Profit Percentage and Markup

Markup is another cost-price-based figure, but it’s calculated before the sale — it’s how much you add on top of your cost to set the selling price, not how much you actually earned after the fact.

Markup % = (Profit ÷ Cost Price) × 100

Notice the formula looks identical to profit percentage — and mathematically, it is the same calculation. The difference is purely in when and why you use it: markup is a pricing decision made in advance (“I’ll add 30% on top of my cost”), while profit percentage is a performance review made after the sale closes. If you’re setting prices with a target margin in mind, our Discount Calculator can help you work backward from a marked price to your actual selling price after any promotional discount.

Profit Percentage Formula Explained

Breaking the formula down conceptually: profit percentage is a ratio. The numerator (profit) captures how much extra money came in beyond what you spent. The denominator (cost price) anchors that gain to your original investment. Multiplying by 100 just converts the ratio into a percentage, which is easier to read and compare than a decimal.

This is also why the same rupee profit can represent wildly different percentages depending on the deal size — a ₹1,000 profit on a ₹2,000 investment is a massive 50% return, while the same ₹1,000 profit on a ₹1,00,000 investment is a modest 1%.

Loss Percentage Formula Explained

The loss percentage formula behaves the same way, just measuring the gap in the opposite direction. Because loss is always defined as CP − SP, the result should be a positive number — if you find yourself with a negative loss percentage, it usually means SP was actually higher than CP, and you should be calculating profit percentage instead.

Solved Examples

Example 1 — Profit: A trader buys a table for ₹1,200 and sells it for ₹1,500.
Profit = 1,500 − 1,200 = ₹300
Profit % = (300 ÷ 1,200) × 100 = 25%

Example 2 — Loss: A retailer buys a jacket for ₹2,000 and sells it for ₹1,700 during clearance.
Loss = 2,000 − 1,700 = ₹300
Loss % = (300 ÷ 2,000) × 100 = 15%

Example 3 — Finding SP from profit %: A wholesaler wants a 20% profit on goods that cost ₹800.
SP = CP × (1 + Profit%/100) = 800 × 1.20 = ₹960

Example 4 — Finding CP from loss %: An item was sold for ₹680 at a 15% loss. What was the cost price?
CP = SP ÷ (1 − Loss%/100) = 680 ÷ 0.85 = ₹800

Student Examples

A student buys a second-hand textbook for ₹150 and resells it at the end of the semester for ₹120.
Loss = 150 − 120 = ₹30
Loss % = (30 ÷ 150) × 100 = 20%

These exact CP/SP-style questions show up constantly in school exams and competitive tests. If you’re revising, our CGPA Calculator and Percentage Calculator are useful companions for the same percentage-based thinking used across most math sections.

Shopkeeper Examples

A grocery shop owner buys a carton of packaged snacks for ₹4,000 and sells the entire stock for ₹4,800.
Profit = 4,800 − 4,000 = ₹800
Profit % = (800 ÷ 4,000) × 100 = 20%

Shopkeepers dealing in GST-registered goods also need to separate tax from actual profit — the GST collected isn’t part of your margin. Our GST Calculator helps split the tax component out cleanly before you calculate profit on the base price. For a fuller walkthrough of how GST interacts with pricing, see our guide on GST explained for beginners.

Small Business Examples

A small furniture workshop spends ₹18,000 on raw materials and labor to build a set of chairs, then sells the set for ₹25,200.
Profit = 25,200 − 18,000 = ₹7,200
Profit % = (7,200 ÷ 18,000) × 100 = 40%

Business owners often need to track this alongside financing costs too. If part of that ₹18,000 was funded through a business loan, checking your true profit means netting out the interest paid — our EMI Calculator and background reading on how EMI is calculated can help you factor loan repayments into your real margin.

E-commerce Examples

An online seller sources a product for ₹450 (including packaging), lists it at ₹899, and after a platform discount of ₹100, the customer pays ₹799.
Profit = 799 − 450 = ₹349
Profit % = (349 ÷ 450) × 100 = ~77.6%

Note the seller’s real profit percentage is calculated on the final SP the customer actually paid (₹799), not the original listed price (₹899). This is one of the most common e-commerce miscalculations — sellers calculate margin off the “before discount” price and end up overestimating profitability. Run your listed price through our Discount Calculator first to find the real selling price, then calculate profit percentage from there.

Practice Questions with Answers

Q1. CP = ₹350, SP = ₹420. Find profit %.
Answer: Profit = 70. Profit % = (70 ÷ 350) × 100 = 20%

Q2. CP = ₹1,000, SP = ₹850. Find loss %.
Answer: Loss = 150. Loss % = (150 ÷ 1,000) × 100 = 15%

Q3. A shopkeeper wants a 30% profit on an item that costs ₹600. What should the SP be?
Answer: SP = 600 × 1.30 = ₹780

Q4. An item sold for ₹918 resulted in an 8% profit. Find the CP.
Answer: CP = SP ÷ (1 + Profit%/100) = 918 ÷ 1.08 = ₹850

Q5. CP = ₹2,500, SP = ₹2,500. What is the profit or loss %?
Answer: 0% — this is a no-profit-no-loss (break-even) transaction.

Common Calculation Mistakes

• Calculating on SP instead of CP. Profit and loss percentages are always based on cost price. Using selling price as the base gives a smaller, incorrect number.
• Confusing marked price with cost price. The marked price (MP) is the listed sticker price before any discount. It has nothing to do with what you paid to acquire the item — always calculate against CP, not MP.
• Ignoring extra costs. Shipping, packaging, platform fees, and transport charges are part of your true cost price. Leaving them out inflates your apparent profit.
• Mixing up profit percentage with profit margin. As covered above, these use different denominators and are not interchangeable.
• Assuming profit % and loss % can occur together. A single transaction is either a profit, a loss, or break-even — never a mix of both.
• Forgetting successive discounts compound, not add. Two 10% discounts don’t equal a 20% discount — the second discount applies to the already-reduced price.

Tips for Accurate Calculations

• Always total your full cost price first — materials, labor, shipping, fees — before running the formula.
• Double-check whether a competitor’s report or dataset uses margin (SP-based) or profit percentage (CP-based) before comparing numbers.
• For recurring calculations, keep a simple spreadsheet with CP, SP, Profit/Loss, and Profit/Loss % columns so you’re not redoing the math every time.
• When averaging profit percentage across multiple products or months, don’t just average the percentages directly — weight them by sales volume or revenue, or use our Average Calculator alongside your raw figures for an accurate blended number. Stock traders comparing purchase prices across multiple buys can use the same averaging logic with our Stock Average Calculator — see our related guide on how to calculate average stock price.
• For investments held over time rather than one-off sales, growth is usually compounding rather than a single profit percentage — our guide on compound interest for beginners and Compound Interest Calculator cover that scenario.

Frequently Asked Questions

What is the basic formula for profit percentage?

Profit % = (Profit ÷ Cost Price) × 100, where Profit = Selling Price − Cost Price.

What is the basic formula for loss percentage?

Loss % = (Loss ÷ Cost Price) × 100, where Loss = Cost Price − Selling Price.

Why is profit percentage calculated on cost price and not selling price?

Cost price represents your actual investment in the item. Measuring gain against what you originally spent — rather than against the sale amount — gives an accurate picture of return on that investment.

Can profit percentage and loss percentage happen in the same transaction?

No. A single sale is either a profit, a loss, or a break-even (no profit, no loss) — the three outcomes are mutually exclusive.

How do I find the selling price if I know the cost price and desired profit percentage?

Use SP = CP × (1 + Profit%/100). For example, a ₹500 item with a target 20% profit should sell for ₹600.

How do I find the cost price if I know the selling price and the loss percentage?

Use CP = SP ÷ (1 − Loss%/100). For example, an item sold for ₹680 at a 15% loss had a cost price of ₹800.

Is profit percentage the same as profit margin?

No. Profit percentage divides profit by cost price; profit margin divides profit by selling price (revenue). They answer different questions and typically produce different numbers for the same transaction.

What if selling price equals cost price?

That’s a break-even transaction — 0% profit and 0% loss.

References

• NCERT Mathematics — Commercial Mathematics: Profit, Loss and Discount
• Central Board of Secondary Education (CBSE) — Class 8 Mathematics Curriculum, Comparing Quantities Unit

Last Updated: July 20, 2026
Reviewed by the CalcyLab Editorial Team

Conclusion

Profit percentage and loss percentage both come down to one comparison: what you gained or lost, measured against what you originally spent. Get the cost price right, keep it as your consistent base, and the rest of the formula takes care of itself — whether you’re solving a textbook question, pricing a product for resale, or reviewing how a business quarter actually performed.

For instant results without manual calculation, try our Profit & Loss Calculator — just enter your cost price and selling price to get exact profit or loss percentage in seconds.