ToolJoltTools

Protein Hydrophobicity (GRAVY) Calculator

Score the GRAVY hydropathy of a protein from its amino-acid sequence. Positive = hydrophobic, negative = hydrophilic. 100% in-browser — your sequence is never uploaded.

GRAVY = mean Kyte–Doolittle index
-0.228
GRAVY hydropathy
hydrophilic
Character
75
Residues
  1. 1
    GRAVY = Σ(Kyte–Doolittle index) ÷ length
    -17.1 ÷ 75 = -0.228
  2. 2
    Negative → hydrophilic overall
Protein: Positive = hydrophobic, negative = hydrophilic.

🔒 100% client-side — your data is computed in the browser and never uploaded.

Cite this toolToolJolt. Protein Hydrophobicity (GRAVY) Calculator. ToolJolt Chemistry & Lab Tools; 2026. https://tooljolt.com

Need a fast, reliable protein hydrophobicity (gravy) calculator? This free tool computes the answer the moment the page loads and updates live as you type — no sign-up, no installs.

About Protein Hydrophobicity (GRAVY) Calculator

Score the GRAVY hydropathy of a protein from its amino-acid sequence. Positive = hydrophobic, negative = hydrophilic. 100% in-browser — your sequence is never uploaded. The calculation uses GRAVY = mean Kyte–Doolittle index. Why this calculation counts: The extinction coefficient sets every A280 concentration you report; the pI decides your ion-exchange and solubility strategy. These numbers underpin purification and quantitation. Protein: Positive = hydrophobic, negative = hydrophilic. Common pitfalls to avoid: using reduced vs oxidized ε in the wrong context; assuming pI from sequence equals experimental pI exactly; ignoring post-translational modifications. All maths runs locally in your browser; no data is ever sent to a server. That privacy is exactly why researchers link these calculators from protocols, theses and standard operating procedures.

How to use Protein Hydrophobicity (GRAVY) Calculator

  1. 1Enter your input values.
  2. 2Read the headline result and the supporting figures, which recompute as you type.
  3. 3Open “Worked example with your numbers” to see the substituted formula step by step.
  4. 4Copy the result, or use the cite-this-tool snippet for your methods section.

Why use Protein Hydrophobicity (GRAVY) Calculator?

  • Links to related protein and peptide characterization calculators so you can finish the whole workflow
  • Copy-ready result and a one-line “cite this tool” snippet for your methods section
  • Designed for protein biochemists, structural biologists and assay developers who need a trustworthy answer fast
  • Instant, client-side result — works offline once loaded and keeps your data private
  • Shows the worked example step by step with your own numbers, not just a final figure

Frequently asked questions

Any tips specific to this calculation?+

Protein: Positive = hydrophobic, negative = hydrophilic. Also watch out for: using reduced vs oxidized ε in the wrong context and forgetting cystine (disulfide) contributions to ε280.

Is this protein hydrophobicity (gravy) calculator free to use?+

Yes. It is completely free, needs no sign-up, and runs entirely in your browser — there are no usage limits.

What formula does it use?+

It uses GRAVY = mean Kyte–Doolittle index The full worked example is shown beneath the result so you can verify each step.

What are the most common mistakes here?+

In protein and peptide characterization, watch for: forgetting cystine (disulfide) contributions to ε280; using reduced vs oxidized ε in the wrong context; assuming pI from sequence equals experimental pI exactly; ignoring post-translational modifications. This tool shows the working so you can catch these before they cost an experiment.

Does my data leave my device?+

No. All computation happens locally in your browser. Nothing you enter — sequences, concentrations or measurements — is uploaded to any server, so it is safe for confidential work.

Can I cite this tool?+

Yes — use the “Cite this tool” snippet on the page. Many users link these calculators from methods sections, lab SOPs and teaching materials.

Related tools

Related Chemistry tools

Sponsored