Electrostatic Surface Calculator

Important: API Instability Notice

The PDB2PQR/APBS web server API is undergoing changes, which may cause connection instability or failures. This is not an error in this tool, it's a temporary limitation.

Automatic Fallback: If the APBS server fails, the tool will automatically switch to a simplified electrostatic model based on residue charges (ARG/LYS: positive, ASP/GLU: negative). While less accurate, this provides immediate results for quick analysis.

Skip the Wait: Click "Use Simplified Mode" button to directly use the fallback model without trying APBS first.

Simple Solution: Install a CORS browser extension (e.g., "CORS Unblock") or use local APBS installation for production work. See CORS_SETUP.md for details.

PDB Input

APBS Parameters

Charge assignment method
Solution pH
Ionic strength

Electrostatic Results

Upload a PDB file and click "Calculate" to start