Peptide Property Calculator

Calculate comprehensive peptide properties including molecular weight, isoelectric point, GRAVY, aliphatic index, instability index, and amino acid composition

Detailed Analysis

Amino Acid Composition

Titration Curve (pH vs Net Charge)

What is Peptide Property Calculator?

A comprehensive bioinformatics tool that calculates physicochemical properties of peptides and small proteins. It analyzes molecular weight, isoelectric point (pI), hydropathicity (GRAVY), aliphatic index, instability index, and amino acid composition to help researchers understand peptide behavior and stability.

How to Use This Tool

Quick guide to analyze your peptide:

  1. Enter peptide sequence using single-letter amino acid codes
  2. Properties are calculated automatically as you type
  3. View detailed analysis cards and composition table
  4. Download or copy the complete report

When to Use

This tool is essential for:

  • Drug discovery and peptide therapeutics development
  • Protein purification strategy planning
  • Stability assessment for peptide storage
  • Biochemical characterization studies
  • Solubility and aggregation prediction

Example Input

Sample insulin A-chain sequence:

GIVEQCCTSICSLYQLENYCN

Try with your own peptide sequence or click Example button.

Properties Calculated

Comprehensive analysis includes:

  • Molecular Weight: Exact mass with peptide bonds
  • Isoelectric Point (pI): pH at zero net charge
  • GRAVY: Hydropathicity index
  • Aliphatic Index: Thermostability indicator
  • Instability Index: In vitro stability
  • Net Charge: At physiological pH 7.0

FAQ

Q: What sequence formats are supported?
A: Single-letter amino acid codes (A, R, N, etc.) and FASTA format.

Q: How accurate are the calculations?
A: Uses established algorithms with published pKa values and scales for high accuracy.

Q: What does instability index mean?
A: Values >40 indicate potentially unstable peptides in vitro.