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Codon usage calculator
Paste a coding sequence and get the full codon table — every codon's count, share, and RSCU (relative synonymous codon usage) — plus GC content at the first, second and third codon positions.
0 bases · Spaces, line numbers and FASTA headers are removed automatically.
Codon table
Good to know
Reading the RSCU column
RSCU = 1 means a codon is used exactly as often as expected if all synonymous codons were equal. Values well above 1 mark preferred codons in your sequence; comparing this profile between a gene and its expression host is the first step of codon optimisation.