Sponsored

GC Content Calculator

Calculate DNA GC content from base counts.

GC Content measurements

Enter your values, then calculate.

Result

Enter your measurements above to calculate.
CategoryBiology
Inputs4
CalculationIn browser
Share this calculator:

How to calculate gc content

GC content is the percentage of a DNA or RNA sequence made up of guanine and cytosine bases — a fundamental measure in molecular biology and genomics.

How the calculation works

GC content = 100 × (Guanine + Cytosine) ÷ (Guanine + Cytosine + Adenine + Thymine).

Example

20 guanine, 25 cytosine, 22 adenine, 18 thymine: 100×(20+25)÷(20+25+22+18) = 100×45÷85 ≈ 52.9%.

Frequently asked questions

How is Result calculated?

Result = 100 × ([Guanine count] + [Cytosine count]) ÷ ([Guanine count] + [Cytosine count] + [Adenine count] + [Thymine count]).

Is the GC Content Calculator free to use?

Yes — every calculator on Simple Calculator Tools is free, runs in your browser, and does not require an account.

Quick Insight

GC Content Calculator

GC content = 100 × (Guanine + Cytosine) ÷ (Guanine + Cytosine + Adenine + Thymine).

Powered by SCT Smart Guide™

Let's understand your gc content result.

Your personalized explanation

Calculate a result above and this guide will help you interpret it using this calculator's own formula and explanation.

Pro Tips for GC Content

  1. GC content varies by organism and affects DNA stability — higher GC content generally means a higher melting temperature.
  2. This is commonly used in primer design for PCR, since GC content affects primer binding characteristics.

Common GC Content Mistakes to Avoid

  • Forgetting to include all four base counts in the denominator, which would produce an incorrect percentage.

When to Use This Calculator

GC content is the percentage of a DNA or RNA sequence made up of guanine and cytosine bases — a fundamental measure in molecular biology and genomics.

Content reviewed: August 2026 · Robert Threadgill
Sponsored