TimelyScholarFree Tools › GC Content Calculator
Calculate the GC content of one or many DNA sequences, with base counts and a sliding-window plot of GC % along the sequence.
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| Sequence | Length | GC % | AT % | A | C | G | T/U | Other |
|---|---|---|---|---|---|---|---|---|
| example_sequence (synthetic) | 246 | 47.56 | 52.44 | 64 | 56 | 61 | 65 | 0 |
GC % = (G + C) / (A + T + G + C) × 100. Ambiguous bases (such as N) are left out of both counts; S counts as G/C and W as A/T.
Plain or multi-FASTA.
GC %, AT % and base counts per sequence.
See how GC content varies along the first sequence.
GC content is the percentage of bases in a DNA molecule that are guanine or cytosine. G–C pairs form three hydrogen bonds and stack more strongly than A–T pairs, so GC-rich sequences are more stable and melt at higher temperatures.
GC content affects primer and probe design, PCR efficiency and sequencing coverage, and differs between genomes and regions of a genome.
They are excluded from the calculation, so GC % reflects only the known bases.