Peptide Dosage Calculator

Research peptide dosing follows a principle of start low and assess. Most protocols recommend beginning at the lower end of the published range and increasing gradually while monitoring for side effects. This is especially important with GLP-1 receptor agonists (semaglutide, tirzepatide) and growth hormone secretagogues (CJC-1295, ipamorelin), where side effects are dose-dependent.

The dosages shown by this calculator are based on published research data and are provided for informational and educational purposes only. They are not medical advice, prescriptions, or recommendations for human use. Individual responses to peptides vary significantly based on genetics, health status, concurrent medications, and other factors that a calculator cannot account for.

Many peptide dosages in research are reported on a per-kilogram basis (mcg/kg), while others use flat doses regardless of weight. This calculator applies a linear body-weight adjustment relative to a 180 lb (81.6 kg) reference, which provides a reasonable approximation for compounds where weight-based dosing is appropriate.

Compounds that typically use weight-based dosing include BPC-157, TB-500, and most growth hormone secretagogues. Compounds that typically use flat dosing — where the same dose is given regardless of weight — include semaglutide, tirzepatide, and PT-141. For flat-dosed compounds, the calculator shows the standard range without weight adjustment.

A loading dose (also called a saturation dose) is a higher initial dose used at the start of a protocol to reach effective tissue concentrations faster. After the loading phase — typically lasting 1 to 4 weeks — the dose is reduced to a lower maintenance dose for the remainder of the protocol.

Loading doses are common with peptides that have a slow onset of action or that need to accumulate in tissue. For example, TB-500 protocols often start with a 2-week loading phase at a higher dose before dropping to a maintenance level. Not all peptides require loading doses — many are effective from the first administration at standard ranges.

For help converting your dose into syringe units after reconstitution, use the Peptide Reconstitution Calculator. For a complete guide on dose measurement and injection technique, read How to Calculate Peptide Dosage. Each compound profile on this site also includes a dedicated dosage page with protocol details — browse them in the compound library.