Peptide math, made clear.
A free calculator for concentration, dilution and sequence chemistry, plus a curated library of peer-reviewed peptide studies. In English and Arabic.
Measurement
Turn vial mass, solution volume and a target amount into concentration, volume and U-100 syringe units.
Dilution
Plan a final volume for a target concentration, or step an existing stock solution down.
Sequence lab
Paste an amino acid sequence for molecular weight, isoelectric point, charge and hydropathy charts.
Precision, made simple.
Concentration, measurement and sequence chemistry in one workspace. Results are arithmetic only, never dosing advice.
Your inputs
Enter your research values, or load a clearly labeled arithmetic example.
A name for your records only, such as compound or batch. Always check the vial mass against its label.
See the calculation
Live reference table
Arithmetic comparison for your current concentration. These amounts are not recommendations.
| Target amount | mL | U-100 units | Capacity check |
|---|
Plan a dilution
Calculate a final volume from a specified concentration, or dilute an existing stock.
For dry material, make up to the calculated final volume. Powder displacement is not modeled. For stock dilution, volumes are assumed additive.
Explore a sequence
20 standard amino acids; one-letter codes or separated three-letter codes. Linear chains only. No FASTA headers, nonstandard residues, cyclization or disulfide bonds.
Net charge vs. pH
Hydrophilicity by residue
Hydropathy by residue
Amino acid composition
| Residue | Count | % |
|---|
Theoretical estimates: average residue masses plus H₂O; Henderson–Hasselbalch charge using fixed pKa values; Hopp–Woods hydrophilicity; Kyte–Doolittle hydropathy. Hydrophilic ratio counts residues with positive Hopp–Woods values. Terminal caps change mass and terminal charge only. No purity, stability or solubility prediction.
Understand the numbers
What does a syringe unit mean?
This calculator uses U-100 only: 100 syringe units = 1 mL. A U-40 syringe uses a different scale. Syringe markings are volume equivalents, not peptide potency or biological IU.
Does adding water change the peptide amount?
Dilution changes concentration, not total mass. Concentration = vial mass ÷ final volume. Measurement volume = target mass ÷ concentration. 1 mg = 1,000 mcg.
Which solvent and storage conditions should I use?
Use the solvent, preparation method and storage conditions specified for the exact compound by its supplier or validated laboratory protocol. There is no universal solvent or shelf life for every peptide.
How do I record a research preparation?
Record compound identity, batch, total mass, final volume, concentration and preparation date. Use validated laboratory handling procedures. This tool calculates quantities; it does not establish a preparation protocol.
Laboratory arithmetic and educational sequence analysis only. Not for human or veterinary administration. This tool does not select a dose or treatment.
Peer-reviewed reading, organized.
A starting set of reviews, landmark trials and method papers. Summaries are short orientations, not conclusions. Always read the original.
Each link opens PubMed with the paper's exact title, so you can reach the abstract and full text from the source.
An independent research resource.
PeptideStudy exists to make peptide arithmetic and literature easier to work with, for Arabic and English readers alike. Nothing is sold here.
Privacy
- No accounts, no cookies and no analytics.
- Every calculation runs in your browser and is never sent anywhere.
- Your language choice is remembered only on your own device.
How the numbers work
- Concentration = vial mass ÷ final volume. Volume = target ÷ concentration.
- U-100 scale only: 100 units = 1 mL. Powder displacement is not modeled.
- Sequence values use average residue masses, fixed pKa values, Hopp–Woods and Kyte–Doolittle scales.
Disclaimer
PeptideStudy is for education and laboratory research arithmetic only. It does not provide medical advice, diagnosis, dosing or treatment recommendations.
Calculated values are theoretical. Verify every figure against the compound's documentation and a validated laboratory protocol. Talk to a qualified healthcare professional about any medical question.