Educational tool

Peptide Levels Calculator

This estimates how many mg are active in the body each day. Pick the peptides you're running, set your dose and how far apart your jabs are, then tap any day for the detail. Model: first-order absorption (slow depot release, peaks ~8–72h post-jab) + exponential elimination, from published trial half-life data.

Each bar shows the average level for that day. Every active peptide gets its own lane and figure, and the bars grow into place from the week you start it. Tap or click any day to see its breakdown. The model assumes each jab is absorbed slowly from the injection site, peaking 8–72 hours after injection, and then decays exponentially. Half-lives come from published clinical trial data: for example, about 6 days for retatrutide, ~7 days for cagrilintide, ~5 days for tirzepatide and ~7 days for semaglutide.
Disclaimer

This is an educational estimation tool only. It is not medical advice, and it is not a dosing guide, a prescription, or a recommendation to use any substance.

Some peptides here, including retatrutide and cagrilintide, are investigational drugs. They're not approved by the MHRA, the FDA or any other regulatory body, and they're not legally available. Others, including tirzepatide and semaglutide, are approved prescription-only medicines, available only under medical supervision. All figures are estimates based on published trial data, and real-world results vary from person to person.

Always consult your doctor or a qualified healthcare professional before starting, changing, or stopping any medication. Never make decisions about your health based on a chart on the internet — including this one.

No liability is accepted for any use of this tool or reliance on its output. If you are experiencing a medical issue, contact your doctor or healthcare professional.

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