Percentage Calculators
Free, instant percentage calculators trusted across the UK. No sign-up, no fuss, just accurate results with step-by-step workings.
Used daily by students, teachers and professionals across the UK
Last updated: May 2026
Why use percentages.co.uk?
Whether you need to work out a sale price, calculate a tax amount, figure out how much something has increased, or split a restaurant bill, our free percentage calculators handle it all instantly. Every calculation shows clear step-by-step workings so you can understand exactly how the answer was reached.
All calculators are free to use, work on any device, and require no account or sign-up. We do not store your calculations or personal data.
How to calculate a percentage
The core percentage formula is: divide the part by the whole, then multiply by 100. This gives you the percentage the part represents of the whole.
Percentage = (Part / Whole) x 100
What is 15% of a £240 restaurant bill?
- Convert: 15 / 100 = 0.15
- Multiply: 0.15 x £240 = £36
Answer: £36
A train fare rises from £12.40 to £13.80. What is the percentage increase?
- Find the difference: £13.80 - £12.40 = £1.40
- Divide by the original: £1.40 / £12.40 = 0.1129
- Multiply by 100: 11.29%
Answer: 11.29% increase
A jacket costs £120 and is reduced to £90. What is the percentage decrease?
- Find the difference: £120 - £90 = £30
- Divide by the original: £30 / £120 = 0.25
- Multiply by 100: 25%
Answer: 25% decrease
A pupil scores 43 out of 60 on an exam paper. What percentage is that?
- Divide: 43 / 60 = 0.7167
- Multiply by 100: 71.67%
Answer: 71.67%
What is a percentage?
A percentage is a number expressed as a fraction of 100. The word comes from the Latin per centum, meaning "by the hundred". When you see 45%, it simply means 45 out of every 100.
Where did the % symbol come from?
The % symbol evolved from the Italian expression per cento meaning "per hundred". Over centuries of handwriting, "per" disappeared and "cento" was compressed into two small circles with a line between them. The symbol appeared in its recognisable form in 15th-century Italian manuscripts and has been in use ever since.
Percentages above 100% are valid
A 200% increase means a value has tripled. A salary rising from £30,000 to £90,000 is a 200% increase. Negative percentages such as -35% are also valid: they simply describe a fall.
The commutative property
X% of Y always equals Y% of X. So 8% of 50 is the same as 50% of 8, which is 4. If a percentage calculation looks difficult, try flipping it. Often the reverse is much easier.
Percentage vs percentage points: a critical distinction
These are not the same thing, and confusing them is one of the most common errors in financial reporting. If an interest rate rises from 10% to 15%:
- The increase is 5 percentage points (arithmetic difference: 15 minus 10 = 5)
- The increase is 50% relative change ((5 / 10) x 100 = 50%)
A headline saying "interest rates rose 50%" sounds alarming. A headline saying "rates rose 5 percentage points" sounds modest. Both describe the exact same change. Knowing the difference helps you read financial news accurately.
Sequential percentage changes do not cancel out
If a price rises 10% then falls 10%, it does not return to where it started.
Start: £200
Rise 10%: £200 x 1.10 = £220
Fall 10%: £220 x 0.90 = £198
The 10% fall applies to £220, not the original £200. The reduction is £22, leaving £198 rather than £200. Each percentage change compounds on the current value.
| Percentage | Fraction | Decimal |
|---|---|---|
| 1% | 1/100 | 0.01 |
| 10% | 1/10 | 0.1 |
| 25% | 1/4 | 0.25 |
| 50% | 1/2 | 0.5 |
| 100% | 1 | 1 |
| 200% | 2 | 2 |
In formal UK English, "per cent" is written as two words. "Percent" as one word is widely accepted. The % symbol is standard in tables, data, and numerical content.
Percentage facts
The % symbol dates to 15th-century Italy
It evolved from handwritten contractions of "per cento", with "cento" gradually becoming two small circles with a line between them.
45% means 45 out of every 100
A percentage is always a ratio expressed as a fraction of 100, regardless of the actual size of the group being measured.
10% of 80 equals 80% of 10
Percentages are commutative: X% of Y always equals Y% of X. Both equal 8. A useful mental maths shortcut when one calculation looks harder than the other.
A 50% rise then 50% fall leaves you 25% worse off
Start with £100. Up 50% gives £150. Down 50% gives £75. Each change applies to the current value, not the original.
Percentages above 100% are mathematically valid
A 150% increase means something has more than doubled. A 200% increase means it has tripled. These are entirely correct uses of the term.
"Per cent" is formally two words in UK English
Style guides including the Oxford Style Manual use "per cent" as two words in running text, though "percent" is widely accepted in everyday use.
All calculators
Basic calculators
Percentage of a Number Calculator
Find what a percentage of any number is instantly.
Percentage Increase Calculator
Calculate how much something has increased in percentage.
Percentage Decrease Calculator
Find the percentage decrease between two values.
Most popularPercentage Change Calculator
Calculate the percentage change between old and new values.
Percentage Difference Calculator
Find the percentage difference between two numbers.
Reverse Percentage Calculator
Work backwards from a result to find the original value.
X is P% of What Calculator
Find the whole number when you know a value and its percentage.
Financial calculators
VAT Calculator
Add or remove UK VAT from any amount quickly.
Discount Calculator
Calculate sale prices and savings from discount percentages.
Tip Calculator
Split bills and calculate tips per person easily.
Percentage Off Calculator
Find the sale price and saving for any percentage off deal.
Markup Calculator
Calculate the selling price from a cost price and markup percentage.
Profit Margin Calculator
Find the gross profit margin and profit from revenue and cost.
Pay Rise Calculator
Calculate your new salary after a percentage pay rise.
Commission Calculator
Calculate commission earned from any sale value and rate.
Cashback Percentage Calculator
Find how much cashback you earn as a percentage of your spend.
Equity Percentage Calculator
Work out ownership percentages and dilution in a company or property.
Basis Points to Percentage Calculator
Convert basis points to percentages and back. 100 bps = 1%.
Payroll Percentage Calculator
Calculate tax, NI and deductions as a percentage of gross pay.
Percentage to Quota Calculator
Work out how close you are to a sales or performance quota.
Target vs Achievement Calculator
Express actual performance as a percentage of any target.
Percent of Income Calculator
Find what percentage of your income goes to any expense or category.
Student calculators
Percentage Grade Calculator
Calculate what percentage your grade is from marks scored.
Test Score Percentage Calculator
Find your test score as a percentage from correct answers.
Percent Error Calculator
Calculate the percent error between an estimated and actual value.
GCSE Grade Calculator
Calculate your GCSE grade from weighted exam papers on the 9-1 scale.
A-Level Grade Calculator
Calculate your A-Level grade from weighted exam components.
UK Degree Calculator
Calculate your UK honours degree classification from module marks.
Win Percentage Calculator
Calculate win rate from wins, losses and draws for any sport or game.
Weight Loss Percentage Calculator
Find what percentage of your starting weight you have lost.
Conversion calculators
Percentage to Decimal Calculator
Convert any percentage to its decimal equivalent instantly.
Decimal to Percentage Calculator
Convert any decimal number to a percentage instantly.
Fraction to Percentage Calculator
Convert any fraction to a percentage with step-by-step workings.
Percentage to Fraction Calculator
Convert any percentage to a simplified fraction instantly.
Ratio to Percentage Calculator
Convert any ratio to a percentage instantly.
Percentage of a Percentage Calculator
Calculate what a percentage of another percentage equals.
Percentage Points Calculator
Find the difference between two percentages in percentage points.
Average Percentage Calculator
Calculate the average of up to five percentage values.
Percentage to Minutes Calculator
Convert a percentage of an hour or day into minutes and seconds.
Percentage Completion Calculator
Track how much of a task, project or goal has been completed as a percentage.
Survey Results Percentage Calculator
Convert survey response counts to percentages and show the full distribution.
Science and data calculators
Mass Percent Calculator
Find the mass percentage of a solute in a solution or mixture.
Percentage Strength Calculator
Calculate % w/v, % w/w and % v/v concentration for any solution.
Percent Water Calculator
Find the percentage of water in a substance using the hydrate crucible method.
Percent Recovery Calculator
Calculate percentage recovery for lab procedures and chemical syntheses.
Mole Percentage Calculator
Find the mole percentage and mole fraction of each component in a mixture.
Frequency Percentage Calculator
Build a percentage frequency distribution from any count or tally data.
Overlap Percentage Calculator
Find the percentage of overlap between two ranges, sets or time periods.
Fold to Percentage Calculator
Convert fold change to percentage change and back. 2× fold = 100% increase.
Calendar Percentage Calculator
Find what percentage of a year, quarter or month has elapsed.
Percent Utilisation Calculator
Calculate how much of a resource, capacity or time budget has been used.
Learn and Practise
New to percentages, helping with homework, or revising for GCSE? Our free guides and interactive practice questions cover every level.
Learn
What Is a Percentage?
A beginner-friendly guide to what percentages mean and how they work.
KS2 Percentages
Simple guide for ages 7-11 covering 50%, 25%, 10% and real life examples.
KS3 Percentages
Percentage increase, decrease, reverse percentages and percentage change for ages 11-14.
GCSE Percentages Revision
Full revision guide covering every percentage topic on GCSE Maths papers.
Practise
KS2 Practice Questions
50 questions across three sets with worked answers for ages 7 to 11.
KS3 Practice Questions
75 questions across three sets for ages 11 to 14.
GCSE Practice Questions
150 exam-style questions across five sets with full worked answers.
AQA Practice Questions
30 questions written in the AQA exam style with Foundation and Higher tiers.
Worksheets
All Percentage Worksheets
Browse 81 free printable worksheets for every year group, topic, difficulty and exam board.
KS2 Percentage Worksheet
20 printable questions with a separate answer sheet for ages 7 to 11.
KS3 Percentage Worksheet
20 printable questions with a separate answer sheet for ages 11 to 14.
GCSE Percentage Worksheet
25 exam-style questions with marks and a separate answer sheet.
Revision
Percentage Quiz
10 random multiple choice questions with instant feedback and score sharing.
Percentage Formula Sheet
All key formulas with worked examples on one printable revision page.
GCSE Revision Notes
Full revision guide covering every percentage topic from Foundation to Higher.
KS3 Revision Notes
Clear revision notes covering all KS3 percentage topics with worked examples.