Codon table

Codon tables describe how the triplet codon of RNA (or DNA) is read by specific tRNAs to map to a particular amino acid. Many organisms use the Standard Codon Table, shown below.

Comprehensive information about codon usage in different organisms can be found at the NCBI Taxonomy site

Standard Codon table

	U	C	A	G
U	UUU Phe F Phenylalanine UUC Phe F Phenylalanine UUA Leu L Leucine UUG Leu L Leucine	UCU Ser S Serine UCC Ser S Serine UCA Ser S Serine UCG Ser S Serine	UAU Tyr Y Tyrosine UAC Tyr Y Tyrosine UAA Ochre (Stop) UAG Amber (Stop)	UGU Cys C Cysteine UGC Cys C Cysteine UGA Opal (Stop) UGG Trp W Tryptophan
C	CUU Leu L Leucine CUC Leu L Leucine CUA Leu L Leucine CUG Leu L Leucine	CCU Pro P Proline CCC Pro P Proline CCA Pro P Proline CCG Pro P Proline	CAU His H Histidine CAC His H Histidine CAA Gln Q Glutamine CAG Gln Q Glutamine	CGU Arg R Arginine CGC Arg R Arginine CGA Arg R Arginine CGG Arg R Arginine
A	AUU Ile I Isoleucine AUC Ile I Isoleucine AUA Ile I Isoleucine AUG Met M Methionine, Start	ACU Thr T Threonine ACC Thr T Threonine ACA Thr T Threonine ACG Thr T Threonine	AAU Asn N Asparagine AAC Asn N Asparagine AAA Lys K Lysine AAG Lys K Lysine	AGU Ser S Serine AGC Ser S Serine AGA Arg R Arginine AGG Arg R Arginine
G	GUU Val V Valine GUC Val V Valine GUA Val V Valine GUG Val V Valine	GCU Ala A Alanine GCC Ala A Alanine GCA Ala A Alanine GCG Ala A Alanine	GAU Asp D Aspartic acid GAC Asp D Aspartic acid GAA Glu E Glutamic acid GAG Glu E Glutamic acid	GGU Gly G Glycine GGC Gly G Glycine GGA Gly G Glycine GGG Gly G Glycine

¹The codon ATG both codes for methionine and serves as an initiation site: the first ATG in an mRNA's coding region is where translation into protein begins.
²UGA can also code for selenomethionine: the twenty-first amino acid, discovered in 1986.
³UAG can also code for pyrrolysine: the twenty-second amino acid, discovered in 2002.