Interactive Codon Table
Explore genetic codes across different species and organelles. Compare standard, mitochondrial, and chloroplast codon tables with interactive filtering and search capabilities.
Species Selection
Codon Table Grid
| 2nd Base | |||||
|---|---|---|---|---|---|
| 1st Base | U | C | A | G | 3rd Base |
| U | UUUPhe (F) UUCPhe (F) UUALeu (L) UUGLeu (L) | UCUSer (S) UCCSer (S) UCASer (S) UCGSer (S) | UAUTyr (Y) UACTyr (Y) UAAStop (*) UAGStop (*) | UGUCys (C) UGCCys (C) UGAStop (*) UGGTrp (W) | U C A G |
| C | CUULeu (L) CUCLeu (L) CUALeu (L) CUGLeu (L) | CCUPro (P) CCCPro (P) CCAPro (P) CCGPro (P) | CAUHis (H) CACHis (H) CAAGln (Q) CAGGln (Q) | CGUArg (R) CGCArg (R) CGAArg (R) CGGArg (R) | U C A G |
| A | AUUIle (I) AUCIle (I) AUAIle (I) AUGMet (M)START | ACUThr (T) ACCThr (T) ACAThr (T) ACGThr (T) | AAUAsn (N) AACAsn (N) AAALys (K) AAGLys (K) | AGUSer (S) AGCSer (S) AGAArg (R) AGGArg (R) | U C A G |
| G | GUUVal (V) GUCVal (V) GUAVal (V) GUGVal (V) | GCUAla (A) GCCAla (A) GCAAla (A) GCGAla (A) | GAUAsp (D) GACAsp (D) GAAGlu (E) GAGGlu (E) | GGUGly (G) GGCGly (G) GGAGly (G) GGGGly (G) | U C A G |
Printable Codon Table Charts
Need downloadable DNA and RNA codon table images? Browse printable chart pages, compare DNA vs RNA layouts, and open style-focused resources without leaving the codon table workflow.
How to Read a Codon Table
A codon table maps each three-base codon to an amino acid (or a stop signal). Codons are typically read as RNA triplets (A, U, G, C). If your sequence is DNA, replace T with U when looking up codons.
Quick lookup example
- Codon: AUG → Methionine (M) and often the start codon
- Codons: UAA / UAG / UGA → Stop codons (end translation)
Common pitfalls
- Reading frame matters: shifting by 1 base changes every downstream codon
- Some organisms use non-standard genetic codes (especially mitochondria)
Standard vs. Mitochondrial Genetic Codes
The “standard” genetic code is widely used, but there are known variations in mitochondria and a few other lineages. If you’re translating mitochondrial genes, selecting the correct genetic code can prevent false stop codons and incorrect amino acid calls.
Next steps
- Translate sequences with a chosen code using DNA to Protein Converter
- Learn how codes vary in Standard Genetic Code Variations
Related Guides
FAQ
What is the difference between a codon table and a codon wheel?
They contain the same mapping. A codon table is faster for scanning and filtering, while a codon wheel is convenient for step-by-step lookup. You can also use our codon wheel for visual lookup.
Do I look up DNA codons with T or U?
Codon tables are usually written in RNA (U). If you have DNA, replace T with U before lookup (e.g., ATG → AUG).
Why does my translation show many stop codons?
The most common reasons are using the wrong reading frame, translating the wrong strand, or using the wrong genetic code (especially for mitochondrial genes). Try translating in all frames and selecting the appropriate code.