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Interactive
Tools that make peptides tangible
Play with sequences, classification, and biophysical approximations — built for learning, not lab reports.
Live playground
Sequence → properties
Type a one-letter sequence. Watch hydrophobicity, charge, mass, and residue chemistry update in real time.
Cleaned length: 9 residuesInvalid characters are ignored automatically
Residue map
Nonpolar Polar Acidic Basic Pro
CYIQNCPLG
Hydrophobicity profile (Kyte–Doolittle)
HydrophilicHydrophobic
Length
9aa
Avg MW
1,010.23Da
Charge @ pH 7.4
-0.25
pI / hydro
5.25 / 0.33
7.4
Educational approximations using average residue masses and standard pKa tables. Real peptides depend on termini, modifications, and experimental conditions.
Classification
Interactive
Peptide Length Explorer
9
amino acids
2oligopolyprotein →60
Classification
Oligopeptide
Short bioactive peptides such as hormones and neuropeptides (e.g. oxytocin).
Note: The boundary between peptides and proteins is not strict and varies by field.
Knowledge check
Quick quiz
1 / 4
What is the typical length range that distinguishes peptides from proteins?
Quick calculator
Tool
Molecular weight estimator
Enter a one-letter amino acid sequence for a quick average-mass estimate.
Estimated MW · 21 aa
2,383.79 Da
Rough average mass (no isotopes or modifications). Updates live.
Did you know?
The word 'peptide' comes from the Greek 'peptos', meaning 'digested'.
These tools use simplified biophysical models for educational purposes. For laboratory or clinical work, use validated software and experimental data.
Cite this: Peptides Codex — Interactive Tools for peptide science education.
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