Protein Extinction Coefficient Calculator

Calculate molar extinction coefficient at 280nm

Amino Acid Sequence

Tryptophan (W)1 (ε = 5,500)

Tyrosine (Y)2 (ε = 1,490)

Cysteine (C)0

Max Disulfide Bonds0 (ε = 125 each)

8,480

M⁻¹ cm⁻¹

All Cys reduced8,480 M⁻¹cm⁻¹

With 0 S-S bonds8,480 M⁻¹cm⁻¹

All Cys oxidized8,480 M⁻¹cm⁻¹

Abs 0.1% (1 g/L) reduced15.116

Abs 0.1% with S-S15.116

A280 per 1 mg/mL1.512

Estimated MW5.6 kDa

C (M) = A280 / ε × path length

Using ε = 8,480 M⁻¹cm⁻¹