Direct answer
How this calculator works
This calculator sums amino acid residue masses and adds terminal water to estimate an unmodified linear peptide's molecular weight.
molecular weight = sum of residue masses + 18.01056 Da
Property result
413.2274 DaEstimated monoisotopic molecular weight for GLPGA.
- Residues
- 5
- Clean sequence
- GLPGA
- kDa
- 0.4132
- Assumption
- Unmodified linear peptide
Common mistakes
- Entering modified residues that are not represented by one-letter amino acid codes.
- Comparing monoisotopic estimates to average mass outputs.
- Ignoring salt forms, terminal modifications, or certificate-specific details.
FAQ
Related questions
What molecular weight does this calculator estimate?
It estimates monoisotopic molecular weight for an unmodified linear peptide sequence using one-letter amino acid codes.
Why might this differ from a certificate of analysis?
A certificate may account for modifications, salt forms, hydration, isotope method, purity, or other analytical details this simple estimate does not include.
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