Best Percentage Calculator 2026 — What Reddit Recommends

For quick percentage math, Google search handles "what is 20% of 350" perfectly. For percentage change, percentage difference, or "what percentage is X of Y," a dedicated percentage calculator is faster and more reliable than trying to phrase the question for Google.

Percentage Calculation Methods Compared

Method	% of a Number	% Change	What % is X of Y	Speed	Best For
Google search	✓ Instant	~Hit or miss	~Hit or miss	✓ Fastest for simple	One-off "X% of Y"
Browser calculator	✓ Instant	✓ Built-in	✓ Built-in	✓ Fast	All percentage types
Phone calculator	~Manual math	✗ Manual formula	✗ Manual formula	~Slow for complex	Basic multiplication
Excel / Sheets	✓ Formula-based	✓ Formula-based	✓ Formula-based	✗ Slow to open	Spreadsheet data
Mental math	~Estimations only	✗ Difficult	✗ Difficult	~Quick for round numbers	Rough estimates

The Three Percentage Questions

1. What is X% of Y?

The most common question. What is 15% of $280? Answer: $42.

Formula: Y x (X / 100) = answer

Common uses: Tips (15-20% of bill), discounts (30% off $80), tax (8.5% of purchase), down payments (20% of home price)

2. What percentage is X of Y?

You scored 42 out of 50 on a test. What percentage? Answer: 84%.

Formula: (X / Y) x 100 = percentage

Common uses: Test scores, completion rates, budget tracking (spent $340 of $500 budget = 68%)

3. Percentage change from X to Y

Your rent went from $1,500 to $1,725. What is the percentage increase? Answer: 15%.

Formula: ((Y - X) / X) x 100 = percentage change

Common uses: Salary increases, price changes, stock performance, weight loss/gain

Quick Percentage Cheat Sheet

To Find...	Shortcut	Example
10% of anything	Move decimal left 1 place	10% of $85 = $8.50
5% of anything	Half of 10%	5% of $85 = $4.25
20% of anything	10% x 2	20% of $85 = $17
25% of anything	Divide by 4	25% of $85 = $21.25
15% tip	10% + half of 10%	15% of $85 = $8.50 + $4.25 = $12.75
1% of anything	Move decimal left 2 places	1% of $85 = $0.85
Percentage of total	Part / whole x 100	42/50 = 84%

Related Calculators

• Percentage Calculator — all three percentage types in one tool
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• Discount Calculator — sale price after percentage off
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• Mortgage Calculator — interest rate percentages
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