Input
Whitespace, digits, and punctuation will be ignored automatically.
Modifications & adjustments
Example data table
These examples demonstrate translation and mass computation with default options.
| Example | DNA | Frame | Strand | Protein | Len (aa) | Monoisotopic (Da) | Average (Da) |
|---|---|---|---|---|---|---|---|
| Example 1 | ATG | 1 | Forward | M | 1 | 149.0511 | 149.2079 |
| Example 2 | ATGGGT | 1 | Forward | MG | 2 | 206.0725 | 206.2598 |
| Example 3 | ATGTAA | 1 | Forward | M | 1 | 149.0511 | 149.2079 |
How to use
- Paste your DNA sequence and choose frame and strand.
- Optionally start at the first ATG and set stop handling.
- Select the genetic code and ambiguity preference.
- Set modifications like Met cleavage, acetylation, phosphorylation, and disulfides.
- Click Compute to translate and calculate protein mass values.
- Download a CSV or PDF summary using the export buttons.
Formula used
The protein mass is computed from residue masses plus water:
Mass = Σ(residue_masses) + Mass(H2O)
- Residue masses use either monoisotopic or average values.
- Mass(H2O) = 18.01056 Da (mono) or 18.01528 Da (avg).
- N-terminal acetylation adds +42.010565 Da (mono) or +42.0367 Da (avg).
- Each phosphorylation adds +79.966331 Da (mono) or +79.9799 Da (avg).
- Each disulfide bond removes 2 hydrogens: −2.01565 Da (mono) or −2.01588 Da (avg).
- N-terminal Met cleavage removes the first residue if it is M.
- Stops (*) are either termination or retained, based on selection.
Ambiguous codons translate to X or are skipped, per setting; X is ignored for mass.
Genetic code variants and key differences
Impactful codon differences that change translation and final mass.
| Codon | Standard code | Vertebrate mitochondrial | Effect on mass |
|---|---|---|---|
| ATA | I | M | May add +17–18 Da if Met replaces Ile |
| TGA | Stop | W | Introduces Trp instead of termination; increases length and mass |
| AGA, AGG | R | Stop | Early termination possible; decreases length and mass |
Choose the correct code to reflect organismal translation accurately.
Residue mass constants and modifications
Values used in calculations for mono and average masses.
| Quantity | Monoisotopic (Da) | Average (Da) | Notes |
|---|---|---|---|
| Peptide water addition | 18.01056 | 18.01528 | Added once per sequence |
| N-terminal acetylation | +42.010565 | +42.0367 | Optional; toggle in settings |
| Phosphorylation (per site) | +79.966331 | +79.9799 | Applied to S,T,Y as count |
| Disulfide bond (per bond) | −2.01565 | −2.01588 | Removes 2 hydrogens |
Residue masses are internal amino-acid residue masses (no terminal water).
IUPAC DNA ambiguity codes and handling
How ambiguous bases are treated during translation.
| Code | Bases | Translator behavior |
|---|---|---|
| R | A or G | Translate codon as X or skip codon, per setting |
| Y | C or T | |
| S | G or C | |
| W | A or T | |
| K | G or T | |
| M | A or C | |
| B | C, G, or T | If X, residue excluded from mass |
| D | A, G, or T | |
| H | A, C, or T | |
| V | A, C, or G | |
| N | Any base | Acts like wildcard; treated as above |
Ambiguous residues do not contribute to mass when translated as X.
Results
Summary
Protein
Length (aa)
–
Stops in sequence
–
Monoisotopic mass (Da)
–
Average mass (Da)
–
Composition