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Peptide Half-Life Calculator & Research Explorer
A peptide's half-life is the time for its plasma concentration to fall by half. Explore reported values for 15 compounds, each tied to its source, population, route and formulation, and see what they mean on an interactive elimination curve.
11 of 15 compounds have a reviewed human half-life · Reviewed 2026-11-08
Tirzepatide
FDA-approved as Mounjaro (type 2 diabetes) and Zepbound (chronic weight management; obstructive sleep apnea with obesity).
Reported half-life: 5 days.
Show chart data as a table
| Series | 1× t½ | 2× t½ | 3× t½ | 4× t½ | 5× t½ |
|---|---|---|---|---|---|
| Tirzepatide | 5 days · 50% | 10 days · 25% | 15 days · 12.5% | 20 days · 6.25% | 25 days · 3.125% |
1 half-life
5 days
50% remaining
2 half-lives
10 days
25% remaining
3 half-lives
15 days
12.5% remaining
4 half-lives
20 days
6.25% remaining
5 half-lives
25 days
3.125% remaining
Source, population and method
The Mounjaro label reports an apparent population mean clearance of 0.061 L/h with an elimination half-life of approximately 5 days.
- Reported value
- 5 days
- Measure
- Elimination half-life (source term: “elimination half-life”)
- Species
- Human
- Population
- Healthy subjects and adults with type 2 diabetes (the label states PK is similar between them)
- Route
- Subcutaneous
- Formulation
- Solution for injection (single-dose pen, vial, KwikPen)
- Context
- Population pharmacokinetic analysis
- Method
- Population pharmacokinetic estimate (apparent population mean clearance)
- Study design
- Regulatory label summary of the clinical pharmacology program
- Source type
- Official prescribing information
- Evidence quality
- High
- Last verified
- 2026-11-08
Steady state is reported after 4 weeks of once-weekly administration; mean absolute bioavailability 80 %.
Source: MOUNJARO (tirzepatide) injection, US prescribing information, section 12.3 · DailyMed SetID d2d7da5d-ad07-4228-955f-cf7e355c8cc0 · 2026-08-27
The two tirzepatide labels give different figures for different populations: about 5 days (Mounjaro) and about 5–6 days (Zepbound, overweight or obesity). Both are shown; neither is averaged.
Idealized first-order elimination, R(t) = 100 × 2−t/t½. It ignores absorption, distribution, metabolites, individual physiology and effect duration, and is never a prediction for a person or a basis for timing anything.
Popular researched compounds
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See the evidence →Dual GIP / GLP-1 receptor agonist
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Dulaglutide
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BPC-157
Half-life not reliably established
Animal data only
See the evidence →What an elimination curve shows
R(t) = 100 × 2^(−t / t½): after each half-life, half of what remained is left. The shape is the same for every compound; only the time scale changes.Show chart data as a table
| Series | 1× t½ | 2× t½ | 3× t½ | 4× t½ | 5× t½ |
|---|---|---|---|---|---|
| Illustrative 1-day half-life | 1 days · 50% | 2 days · 25% | 3 days · 12.5% | 4 days · 6.25% | 5 days · 3.125% |
Compare side by side
Idealized elimination curves
Each curve is the same mathematical model drawn from each compound's reported half-life. These are not measured comparative concentrations: routes, formulations, populations and absorption differ, and none of this ranks one compound above another.
- Semaglutide
- Tirzepatide
- Liraglutide
Show chart data as a table
| Series | 1× t½ | 2× t½ | 3× t½ | 4× t½ | 5× t½ |
|---|---|---|---|---|---|
| Semaglutide | 7 days · 50% | 14 days · 25% | 21 days · 12.5% | 28 days · 6.25% | 35 days · 3.125% |
| Tirzepatide | 5 days · 50% | 10 days · 25% | 15 days · 12.5% | 20 days · 6.25% | 25 days · 3.125% |
| Liraglutide | 0.542 days · 50% | 1.08 days · 25% | 1.63 days · 12.5% | 2.17 days · 6.25% | 2.71 days · 3.125% |
| Compound | Reported half-life | Estimate | Measure | Population | Route · form | Evidence | Status | Limitations |
|---|---|---|---|---|---|---|---|---|
| SemaglutideResearch profile ↗ | 1 week | Elimination half-life | Adults with type 2 diabetes (clearance about 0.05 L/h stated for this population) | Subcutaneous · Solution for injection (pen) | High | FDA-approved | Steady state reported after 4–5 weeks of once-weekly administration; absolute bioavailability 89 %. | |
| TirzepatideResearch profile ↗ | 5 days | Elimination half-life | Healthy subjects and adults with type 2 diabetes (the label states PK is similar between them) | Subcutaneous · Solution for injection (single-dose pen, vial, KwikPen) | High | FDA-approved | Steady state is reported after 4 weeks of once-weekly administration; mean absolute bioavailability 80 %. | |
| LiraglutideResearch profile ↗ | 13 hours | Elimination half-life | Not specified in the half-life statement | Subcutaneous · Solution for injection (pen) | High | FDA-approved | Cmax at 8–12 h; absolute bioavailability about 55 %. Generic liraglutide labels carry the same section 12.3 text. |
How the calculation works
1. A sourced half-life
Pick a reported estimate. Its source, population, route and formulation travel with it, and conflicting estimates stay separate.
2. First-order decay
The fraction remaining after time t is 2^(−t/t½). Halving repeats every half-life, so 1–5 half-lives leave 50 % down to about 3 %.
3. Read it as math
The curve explains the number. It does not model absorption, distribution, metabolites, effect duration or any individual.
Sources and limitations
The curve is an idealized first-order elimination model. It is a mathematical illustration of what a half-life means, not a medical prediction. It does not model:
- Patient-specific pharmacokinetics
- Drug absorption from the site of administration
- Multi-compartment distribution
- Active metabolites
- Receptor occupancy
- How long a clinical effect lasts
- Individual blood concentrations
- Drug interactions
- Changes in kidney or liver function
Values are read from FDA prescribing information on DailyMed, peer-reviewed pharmacokinetic studies and FDA documents, and each is re-checked before it changes. Abstract-only readings are flagged on the record. All sources.
Frequently asked questions
What is a peptide half-life?
The elimination half-life is the time it takes for the concentration of a compound in plasma to fall by half once absorption and distribution are complete. For peptides it ranges from minutes for unmodified sequences to about a week for analogues engineered to bind albumin.
Where do the half-life values come from?
Every value comes from a primary source: official prescribing information first, then peer-reviewed human pharmacokinetic studies, registered trial results and other primary research. Each value shows the population, route, formulation and the source’s own term for what was measured.
Why do some compounds say “half-life not reliably established”?
Because no qualified human study reports one. Rather than repeat unsourced figures or carry over animal values, the site shows the gap and, where they exist, labelled animal values for context.
Does the chart predict levels in my body?
No. The curve is an idealized first-order model that shows what a half-life means mathematically. It ignores absorption, distribution, metabolites and individual physiology, and must never be used to time or plan anything.
Is five half-lives a safe washout period?
No. After five half-lives the idealized model leaves about 3 % of a starting amount, but that is arithmetic, not a safety threshold. Effects, metabolites and individual factors are not part of the model.
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