Codon Usage Calculator

Paste a DNA or RNA coding sequence to get a full codon frequency table and amino acid composition summary.

Input Sequence

0 nt · 0 codons

Paste a sequence and click Analyze

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Summary

Paste a DNA or RNA coding sequence to get a full codon frequency table and amino acid composition summary.

How it works

  1. Paste or type your DNA (ATGC) or RNA (AUGC) sequence into the input box.
  2. The tool reads the sequence in triplet (codon) frames starting at position 1.
  3. Each triplet is looked up in the standard genetic code table.
  4. Codon counts and per-thousand frequencies are computed for all 64 codons.
  5. Amino acid totals are aggregated and displayed in a sortable summary table.

Use cases

  • Evaluate codon bias before ordering a synthetic gene construct.
  • Compare codon usage between two organisms for heterologous expression.
  • Check which codons are most frequent in a CDS for tRNA availability.
  • Analyze amino acid composition of a translated protein-coding region.
  • Quickly verify that an ORF uses expected stop codons.
  • Screen for rare codons that may slow translation in E. coli or yeast.

Frequently Asked Questions

Last updated: 2026-07-01 · Reviewed by Nham Vu