GLP-1 dose calculator

Microdose. Low-dose. Full-dose.

A single “starting dose” isn’t how OPTML thinks about GLP-1s. Lean optimizers chasing food noise and metabolic efficiency need a different titration than someone targeting 20% body-weight loss. This calculator returns the dose band that fits your goal, with the reasoning shown.

~90 seconds Sema or tirzepatide Same flat retail at every dose
$199 / $299
Flat monthly retail, sema / tirz, any dose
1-2 days
Provider review and same-day prescriptions in most states
<5%
Microdose-band patients report significant GI side effects

Profile inputs

Body
lbs
in
yrs
Primary goal
Tolerance & lifestyle

Fill in your profile to see a starting-dose recommendation: microdose, low-dose, or full-dose.

OPTML retail is flat by molecule, sema $199/mo, tirz $299/mo, whether you’re on a microdose or a full titration.

The three dose bands

Which band fits what.

Same molecules. Same retail price. Different starting doses, different titration trajectories, and different clinical outcomes.

Microdose

Sub-clinical optimization

~10-25% of full-dose target

For lean and normal-weight optimizers. Goal isn’t weight loss, it’s metabolic and anti-inflammatory effects: insulin sensitivity, mitochondrial efficiency, food-noise reduction.

  • Sema: 0.10-0.25 mg/wk
  • Tirz: 0.5-1.5 mg/wk
  • Minimal GI side effects
  • Lean mass preservation easier
Low-dose

Recomp / modest goals

~25-50% of full-dose target

Bridge band. For people targeting modest fat loss (5-10 lbs), recomposition, or metabolic improvement with some appetite control. Better tolerated than full-dose.

  • Sema: 0.25-1.0 mg/wk
  • Tirz: 2.5-5.0 mg/wk
  • Mild-to-moderate appetite suppression
  • Most physique-focused users land here
Full-dose

Significant weight loss

FDA clinical titration

For patients targeting 15-25%+ of body weight. The well-trodden titration ladder used in STEP, SURMOUNT, and other landmark trials. Strongest weight-loss outcomes; highest GI burden.

  • Sema: titrate to 2.4 mg/wk
  • Tirz: titrate to 10-15 mg/wk
  • Strong appetite suppression
  • Greatest scale-on-the-floor outcomes
Sema vs tirzepatide

Two molecules. Different profiles.

OPTML’s starting-dose recommendation is independent of molecule choice, pick the molecule with your provider based on tolerance, goals, and history.

Attribute
Semaglutide
Tirzepatide
Receptor activity
GLP-1 only
GLP-1 + GIP (dual)
GI tolerability
Standard GLP-1 profile
Often better at low doses
Weight-loss outcomes
~15% mean (STEP)
~21% mean (SURMOUNT)
Human safety record
Longer (10+ years)
Newer (3+ years)
OPTML retail
$199/mo flat
$299/mo flat

Why a calculator instead of one starting dose?

Most online GLP-1 clinics start every patient on the same FDA titration regardless of goal: 0.25 mg sema or 2.5 mg tirz, ramping every 4 weeks. That’s the right plan for someone targeting 25% body-weight loss. It’s often too aggressive for a lean optimizer who just wants to dial in food noise and insulin sensitivity.

The OPTML model: pick the molecule, pick the goal, and titrate appropriately. Same flat retail at any dose, you pay by molecule, not by milligram, so there’s no incentive to push higher than your goal needs.

How the calculator decides

It looks at four signals:

This is a starting point, not a prescription. Your OPTML provider reviews your full intake, history, and labs before writing the actual protocol. The calculator’s value is making the OPTML positioning legible: starting dose is a clinical choice, not a one-size template.

Pay by the molecule. Not the milligram.

Compounded semaglutide $199/mo flat. Compounded tirzepatide $299/mo flat. Microdose, low-dose, or full-dose, same retail. Provider-titrated. Same-day prescriptions in most states.

Explore microdose GLP-1 →
Educational purposes only. The GLP-1 Dose Calculator provides educational estimates based on published clinical formulas and peer-reviewed research. It is not medical advice, does not constitute a prescription, and is not a substitute for evaluation by a licensed clinician. All medical decisions, including any treatment, medication, or dosing recommendations, are made exclusively by a U.S. licensed physician after individual patient evaluation through OPTML's intake process.
Methodology & Sources Click here for the formulas, datasets, and peer-reviewed studies behind this tool View details ↓Hide ↑

How this tool calculates

This educational tool visualizes the published dose-escalation schedules used in the pivotal clinical trials of the FDA-approved branded GLP-1 medications (STEP-1 for semaglutide, SURMOUNT-1 for tirzepatide). It does NOT prescribe or recommend a specific dose for any individual. All dosing decisions are made exclusively by a U.S. licensed physician after individual patient evaluation.

Peer-reviewed sources

  1. 1.Wilding JPH, Batterham RL, Calanna S, et al. Once-Weekly Semaglutide in Adults with Overweight or Obesity. N Engl J Med. 2021;384(11):989-1002. (STEP-1)
  2. 2.Jastreboff AM, Aronne LJ, Ahmad NN, et al. Tirzepatide Once Weekly for the Treatment of Obesity. N Engl J Med. 2022;387(3):205-216. (SURMOUNT-1)
  3. 3.Davies M, Færch L, Jeppesen OK, et al. Semaglutide 2·4 mg once a week in adults with overweight or obesity, and type 2 diabetes (STEP 2). Lancet. 2021;397(10278):971-984.
  4. 4.U.S. Food & Drug Administration. Compounded Drug Products: What You Need to Know. FDA.gov. 2024.

Important. This tool is provided for educational purposes only and does not constitute medical advice, diagnosis, or treatment. The tool does not prescribe medication, recommend specific dosing, or substitute for clinical evaluation. Compounded medications referenced anywhere on this site are not FDA-approved; the FDA does not verify the safety, effectiveness, or quality of compounded drugs. Treatment decisions are made only by a licensed U.S. physician after individual patient evaluation.