Exponent Calculator

Calculate the result of raising a number to any power. Supports positive, negative, and decimal exponents.

Result

28 = 256

Quick Examples

What Are Exponents?

An exponent tells you how many times to multiply a number (the base) by itself. For example, 2³ means 2 × 2 × 2 = 8. The small raised number is called the exponent or power.

bn = b × b × b × ... (n times)

Exponent Rules

Product: am × an = am+n

Quotient: am ÷ an = am-n

Power of Power: (am)n = am×n

Zero Exponent: a0 = 1

Negative Exponent: a-n = 1/an

Powers of 2

ExponentValueCommon Name
2¹⁰1,0241 KB
2²⁰1,048,5761 MB
2³⁰1,073,741,8241 GB

Fractional and Decimal Exponents

Exponents don't have to be whole numbers. Fractional exponents are another way to write roots:

Square root: a^(1/2) = √a    e.g. 16^(1/2) = √16 = 4

Cube root: a^(1/3) = ∛a    e.g. 27^(1/3) = ∛27 = 3

General rule: a^(m/n) = (ⁿ√a)^m    e.g. 8^(2/3) = (∛8)² = 2² = 4

Calculator tip: Enter 0.5 to compute a square root, 0.333 for a cube root, or any fraction as a decimal.

Powers of 10: Scientific Notation Reference

Powers of 10 are the backbone of the metric system and scientific notation. Each step up multiplies the value by 10.

PowerValueMetric PrefixExample
10⁻⁶0.000001micro (μ)1 μm = 1 micron
10⁻³0.001milli (m)1 mm = 0.001 m
10⁰1Base unit
10³1,000kilo (k)1 km = 1,000 m
10⁶1,000,000mega (M)1 MHz = 10⁶ Hz
10⁹1,000,000,000giga (G)1 GB = 10⁹ bytes
10¹²1 trilliontera (T)1 TB = 10¹² bytes

Real-World Applications of Exponents

Compound Interest

Future value = P × (1 + r)^n. A $1,000 investment at 7% annual return for 30 years grows to $1,000 × 1.07^30 ≈ $7,612 — entirely due to the power of exponents.

Computer Science & Storage

Binary (base 2) uses exponents of 2. A 64-bit processor handles 2^64 ≈ 18.4 quintillion values. Storage units (KB, MB, GB, TB) are all powers of 2 or 10.

Population & Bacterial Growth

Bacteria doubling every hour grow by 2^n in n hours. Starting from 1 cell: after 20 hours there are 2^20 = 1,048,576 cells.

Richter Scale & Sound (dB)

These logarithmic scales are the inverse of exponents. A magnitude 7 earthquake releases 10× more energy than magnitude 6. Every +10 dB sound is 10× more intense.

Step-by-Step Examples

Example 1: Compound Interest (Positive Exponent)

$1,000 invested at 7% annual return for 20 years

FV = 1000 × 1.07²⁰

1.07²⁰ = 3.8697

FV = $3,869.68

Example 2: Negative Exponent (Metric Prefix)

1 microsecond = 10⁻⁶ seconds

10⁻⁶ = 1 / 10⁶ = 1 / 1,000,000 = 0.000001

Example 3: Fractional Exponent (Square Root)

√144 = 144^(0.5) = 144^(1/2)

144^(1/2) = 12 (because 12 × 12 = 144)

Complete Exponent Rules Reference

RuleFormulaExample
Productaᵐ × aⁿ = aᵐ⁺ⁿ2³ × 2⁴ = 2⁷ = 128
Quotientaᵐ ÷ aⁿ = aᵐ⁻ⁿ3⁵ ÷ 3² = 3³ = 27
Power of power(aᵐ)ⁿ = aᵐˣⁿ(2³)² = 2⁶ = 64
Zero exponenta⁰ = 17⁰ = 1
Negative exponenta⁻ⁿ = 1/aⁿ2⁻³ = 1/8 = 0.125
Fractional exponenta^(1/n) = ⁿ√a8^(1/3) = ∛8 = 2
Power of product(ab)ⁿ = aⁿ × bⁿ(2×3)² = 4 × 9 = 36

Common Exponent Mistakes

aᵐ × bⁿ ≠ (ab)ᵐ⁺ⁿ

The product rule only applies when the base is the same. 2³ × 3² cannot be simplified to a single power — they have different bases.

Negative exponent ≠ negative result

3⁻² = 1/9, not −9. A negative exponent means reciprocal, not sign change.

(a + b)ⁿ ≠ aⁿ + bⁿ

This is one of the most common algebra errors. (2 + 3)² = 25, but 2² + 3² = 13. The power must be distributed using the binomial theorem, not term by term.

Frequently Asked Questions

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