Half-life visualizer

See how a dose
fades over time.

Pick a compound or enter your own half-life and watch the curve. Add a dosing interval to see accumulation toward steady state. A simplified, population-average model for education only — not a measured level, and never a dose recommendation.

Compound & half-life
Steady-state overlay
0%25%50%75%100%t½2t½3t½4t½5t½
7 d half-life
Percent of a single dose remaining at each half-life.
Half-livesElapsed% remaining
1× t½7 d50.0%
2× t½14 d25.0%
3× t½21 d12.5%
4× t½28 d6.3%
5× t½35 d3.1%
Single-dose decay
7 d
Semaglutide — population-average estimate
% left at 1× t½
50.0%
Time to ~5%
30.3 d
Steady state (~5× t½)
35 d
Simplified single-compartment model for education; real absorption, distribution, and individual variation differ.

Lumara is a tracking tool and does not provide medical advice, diagnosis, or treatment. This is a simplified, single-compartment, population-average model — an educational estimate, not a measured blood level — and it never recommends a dose. Always follow your provider's guidance.

Save to your Lumara protocol
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Saving keeps the compound and its half-life in your protocol so the timeline is ready when you log a dose.
The app does this for you

Do the math once. Let the app do it forever.

Save this vial and dose to Lumara and every future draw is pre-computed — with reminders that fire on time and expiry tracking, all on your device.

  • Never re-do the math. Your vial & dose are saved; every draw is ready.
  • Reminders that fire on time — on-device, offline, timezone-aware.
  • See the response — adherence next to your wearable HRV & sleep.
Download on the App Store Get it on Google Play

Free to download for iPhone & Android. A 7-day trial runs in the app — no card. Tracking & education only, never a dose recommendation.

How to read a half-life decay curve

A half-life is the time for the amount in your body to fall by half. In a simple single-compartment model, each half-life halves what remains, so the curve drops quickly at first and then flattens.

  1. Pick a compound from the cited list, or enter your own half-life.
  2. Read the decay curve to see how much remains at each point after a dose.
  3. Add a dosing interval to overlay accumulation toward steady state across repeated doses.
  4. Treat it as a model — it shows the shape of decay, not your actual blood level.

Worked example: a 100 unit dose with a 24-hour half-life

Starting from 100 units of “amount in body,” with a 24-hour half-life:

This is a population-average model, not a measured level — individual metabolism, absorption, and ester kinetics vary. Enter your own compound and interval above.

Frequently asked questions

What is a drug half-life?

A half-life is the time it takes for the amount of a substance in your body to drop by half. After one half-life, 50% remains; after two, 25%; after three, 12.5%, and so on. It sets how quickly a dose clears and how doses accumulate with repeated use.

What is steady state?

Steady state is when the amount you take each interval balances the amount your body clears, so levels plateau. With regular dosing it is reached after roughly five half-lives — which is why some protocols take weeks to “settle in.”

Is this my actual blood level?

No. This is a simplified single-compartment, population-average model that shows the shape of decay and accumulation. Real levels depend on your metabolism, absorption, and the specific ester or formulation, and can only be known by a blood test.

Is this half-life calculator medical advice?

No. It is an educational visualization. It never recommends a dose or interval. Always follow your licensed provider’s instructions.

Related calculators

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