Gc Content Percentage
Calculator
Results
- GC content (%)
- 50
- AT content (%)
- 50
- Sequence length (nucleotides)
- 60
- G + C bases
- 30
Biology and lab results
| GC content (%) | 50 |
| AT content (%) | 50 |
| Sequence length (nucleotides) | 60 |
| G + C bases | 30 |
formula-map diagram
- GC content (%)
- 50
- AT content (%)
- 50
- Sequence length (nucleotides)
- 60
- G + C bases
- 30
Formula breakdown
Formula
GC % = (G + C) ÷ (A + T + G + C) × 100= 50
Note
Simplified model: these results use standard textbook laboratory relationships and average constants (A260 = 1 for 50 µg/mL dsDNA, 617.96 g/mol per base pair, ~110 Da per amino acid, ideal exponential growth). Real samples vary with purity, contaminants, buffer, temperature and instrument calibration. Always confirm against your own standards and protocol; do not use for diagnostic or safety-critical work.
More in Biology and lab
See all →Frequently asked questions
How is GC content calculated?+
GC content is the percentage of guanine and cytosine bases in a sequence: (G count + C count) / total base count x 100. The calculator counts each base type in the sequence you provide and applies this ratio.
Why does GC content matter for PCR and sequencing?+
Higher GC content increases the thermal stability of a DNA duplex because G-C pairs form three hydrogen bonds versus two for A-T, which raises melting temperature and can make high-GC regions harder to denature and amplify, often requiring adjusted PCR conditions or additives.
What counts as a 'normal' GC content range?+
It varies widely by organism, from around 25% in some AT-rich genomes to over 70% in GC-rich ones, so there is no universal normal value; what matters more for lab work is whether a specific primer or amplicon's GC content falls in a workable 40-60% range for typical PCR.
How does the calculator handle ambiguous bases like N?+
Ambiguous IUPAC codes (N, R, Y, etc.) are typically excluded from both the numerator and denominator, or handled according to the tool's stated convention, since they do not represent a definite G, C, A, or T; check that convention if your sequence contains many ambiguous calls.
Can GC content alone predict melting temperature?+
Not precisely: GC content correlates with Tm but ignores sequence-specific effects and length, so two sequences with identical GC content can still have different melting temperatures; GC content is best used as a quick screening metric alongside a dedicated Tm calculation.