Half-Life Visualizer

Half-life is the time it takes for the amount of a compound in your system to drop by 50 percent. A peptide with a 4 hour half-life clears quickly and needs frequent dosing, while one with a 7 day half-life like semaglutide stays active long enough for weekly injections.

Steady state is reached after roughly 5 half-lives, regardless of dose. At that point the amount you take in each interval matches the amount cleared, so the peaks and troughs stop climbing. For a 7 day half-life compound that is about 35 days, or five weekly injections.

The accumulation factor tells you how much higher your steady-state levels sit compared to a single dose. It is calculated as 1 divided by (1 minus 0.5 raised to the interval-over-half-life power). A factor of 2x means the compound builds to twice the level of one isolated dose before clearance balances intake.

Css is the average amount of compound in your system across a dosing interval once you have reached steady state. It scales with your dose and half-life and inversely with how often you inject, following Css equals dose times 1.44 times half-life divided by interval.

No. It models the relative amount of drug in the body using a single-compartment first-order clearance model with full absorption. It is built to show the shape of accumulation and steady state across protocols, not to predict absolute plasma concentrations in mg per liter. Treat it as an educational visualizer, not medical advice.

The peak is the highest level right after a dose and the trough is the lowest level just before the next one. A wide gap between them means large swings in exposure, while a long half-life relative to the dosing interval flattens the curve and keeps levels more stable between injections.