Exponent / Power Calculator
Calculate any number raised to any power. See common powers of your base number.
Source: BBC Bitesize — Powers and roots
By Konstantin Iakovlev · Founder, Calks.uk
Last updated: · Verified against HMRC and GOV.UK 2026/27 rates
Powers of 2
22
4
23
8
24
16
25
32
210
1,024
2-1
0.5
2-2
0.25
20.5
1.4142135624
Disclaimer
This calculator is provided for informational purposes only and should not be considered as financial or tax advice. All calculations are performed locally in your browser — no personal data is collected or sent to our servers. Rates and thresholds are sourced from HMRC and GOV.UK and are updated for the current tax year. Always verify results with HMRC or consult a qualified professional before making financial decisions.
How It Works
Exponents (powers) represent repeated multiplication. The expression a^n means multiplying a by itself n times. This calculator handles positive, negative and fractional exponents as well as expressions involving multiple operations.
Negative exponents produce reciprocals: a^(−n) = 1/a^n. Fractional exponents represent roots: a^(1/2) is the square root of a, and a^(1/3) is the cube root. The calculator shows full step-by-step working so you can follow the logic.
What is an exponent? Repeated multiplication. 5² = 5 × 5 = 25. 2³ = 2 × 2 × 2 = 8. 10⁴ = 10,000. Notation: base^exponent. Special cases: any number to power 0 = 1 (by definition). Any number to power 1 = itself. 0^0 = undefined (or 1 by convention in many contexts). Negative exponents: 5⁻² = 1/5² = 1/25. Fractional exponents: 9^(1/2) = √9 = 3. UK GCSE Maths covers integer exponents; A-level adds fractional and irrational exponents.
Laws of exponents. Multiplication: a^m × a^n = a^(m+n). Sample: 2³ × 2⁴ = 2⁷ = 128. Division: a^m ÷ a^n = a^(m−n). Sample: 5⁵ ÷ 5² = 5³ = 125. Power of power: (a^m)^n = a^(m×n). Sample: (3²)³ = 3⁶ = 729. Distributive: (ab)^n = a^n × b^n. Negative: a^(−n) = 1/a^n. Zero: a⁰ = 1 (for a ≠ 0). Always taught in UK GCSE Higher Tier as 'index laws' or 'exponent laws'.
Scientific notation. Express very large or very small numbers compactly. 1,000,000 = 1 × 10⁶. 0.000001 = 1 × 10⁻⁶. UK distances: Earth to Moon 3.844 × 10⁸ m; Earth to Sun 1.496 × 10¹¹ m; Hydrogen atom radius 5.3 × 10⁻¹¹ m; mass of electron 9.109 × 10⁻³¹ kg; speed of light 2.998 × 10⁸ m/s. UK A-level Physics, Chemistry, Maths use scientific notation extensively. Calculator EXP or EE button enters scientific notation.
Powers of 2 and computer science. 2¹ = 2, 2² = 4, 2³ = 8, 2⁴ = 16, 2⁵ = 32, 2⁶ = 64, 2⁷ = 128, 2⁸ = 256, 2¹⁰ = 1,024, 2¹⁶ = 65,536, 2³² = 4.3 billion (32-bit max), 2⁶⁴ = 18 quintillion (64-bit max). Storage: kilobyte ≈ 2¹⁰ bytes = 1,024 B; megabyte 2²⁰; gigabyte 2³⁰; terabyte 2⁴⁰. RAM addressing: 32-bit systems max 4GB; 64-bit systems virtually unlimited. UK Computer Science GCSE/A-level requires familiarity.
Compound interest — real-world exponents. Future value = Principal × (1 + rate)^years. £10,000 at 5% for 30 years: £10,000 × 1.05³⁰ = £10,000 × 4.32 = £43,219. Same money at 7% for 30 years: 1.07³⁰ = 7.61 → £76,123. Just 2% extra annual return = 76% more wealth. Rule of 72: years to double = 72 ÷ rate. 5% → 14.4 years; 7% → 10.3; 10% → 7.2. Pension projections, mortgage calculations, investment forecasts — all use exponential growth.
Example: Calculating 5^4
- 5^4 = 5 × 5 × 5 × 5
- = 25 × 25
- = 625
Source: BBC Bitesize — Powers and roots
Frequently Asked Questions
- What does the Exponent / Power Calculator do?
- Calculate any number raised to any power. See common powers of your base number.
- How accurate are the results?
- This calculator uses standard mathematical algorithms and provides results accurate to the precision shown. For very large numbers or high-precision requirements, results are rounded to a reasonable number of decimal places.
- Can I use this for schoolwork?
- Yes. This calculator is suitable for GCSE, A-level and university-level mathematics. It follows standard mathematical conventions used in UK education.