Semaglutide dosing calculator

Educational reference only

Semaglutide is a prescription medication in most countries. This page is for educational reference only. Underground Biohacking does not provide dosing protocols, interaction warnings, or usage guidance for prescription compounds. If you are using or considering Semaglutide, work with a licensed clinician.

CompoundSemaglutide

Vial

Water

Your dose

1 mg = 1000 mcg.

Your syringe

Draw this much

Enter a vial size, water volume and dose to see where to pull.

0 units0.3 mL barrel, U-100 scale30 units

For tracking and calculation purposes only. Not medical advice. Based on a standard U-100 insulin syringe.

Label schedule, for reference

This is the FDA-label schedule for the approved product, shown for reference. It is not a dose suggestion.

Week	Amount, once weekly
1-4	0.25 mg
5-8	0.5 mg
9-12	1 mg
13-16	1.7 mg
17+	1.7 or 2.4 mg

Week 17 onward is maintenance: 1.7 mg or 2.4 mg once weekly. Ozempic runs a different schedule: 0.25 mg weekly for 4 weeks, then 0.5 mg, then 1 mg after at least 4 more weeks, then 2 mg, with 2 mg weekly the maximum.

Source: Wegovy (semaglutide) label, DailyMed section 2.2, Table 1 Also: Ozempic (semaglutide) label, DailyMed section 2.2.

How the units are worked out

Your vial holds a fixed amount of peptide. The water you add sets the concentration (how much peptide sits in each millilitre). The concentration then decides how much liquid carries your dose.

Three steps, in order:

Concentration (mcg/mL) = peptide in the vial (mcg) divided by water added (mL).
Volume (mL) = your dose (mcg) divided by the concentration (mcg/mL).
Units to draw = volume (mL) multiplied by 100.

That last step is the syringe, not the peptide. A U-100 insulin syringe is marked so 100 units hold 1 mL, so 0.1 mL reads as 10 units.

A worked example

Enter your dose in the calculator above and this line shows the numbers worked through.

Water and units at a glance

Semaglutide at different mixes. Every row opens the calculator on that mix.

Vial	Water	Concentration
10 mg	1 mL	10,000 mcg/mL
10 mg	2 mL	5,000 mcg/mL
10 mg	3 mL	3,333 mcg/mL
10 mg	5 mL	2,000 mcg/mL

Units appear once you enter a dose.

Pre-filled numbers are the most-used setups reported by users of public calculators (WPA dosing data, Aug 2026). Not a recommendation.

Mixing and storage

Run the water down the inside wall of the vial and let the powder dissolve on its own. Never shake it. Label the vial with the compound, the total mass, the water you added, the concentration and the date. A sealed freeze-dried vial keeps 12 to 24 months in the fridge at 2 to 8°C. Once mixed with preserved water, such as bacteriostatic water, that drops to roughly 28 days refrigerated. Keep it at the back of the fridge, away from light and away from the door's temperature swings.

Other compounds

Questions

What does semaglutide actually do in the body?

It copies a gut hormone called GLP-1. That hormone does three useful things at once. It nudges the pancreas to release insulin when blood sugar rises. It slows how fast the stomach empties, so food sits longer. And it acts on appetite centres in the brain, so hunger drops and meals end sooner. Animal work confirms the brain part directly. The net result is lower blood sugar and less food eaten.

What did the main obesity trial actually show?

It enrolled 1961 adults with overweight or obesity, and without diabetes. They took semaglutide or placebo for 68 weeks, alongside lifestyle support. Average body weight fell by about 15 percent on the drug, against about 2 percent on placebo. Around half the semaglutide group lost 15 percent or more of their starting weight. That was a larger effect than any earlier weight drug had shown at that scale. Individual results varied a lot.

Does it actually protect the heart?

Yes, in the groups that were studied. One trial enrolled over 17,000 adults with existing heart disease and obesity but no diabetes. Cardiovascular death, heart attack or stroke happened in 6.5 percent on semaglutide, against 8.0 percent on placebo. An earlier trial in people with type 2 diabetes at high risk found a similar drop. Neither trial studied healthy people at normal weight, so the benefit is unproven there.

What happens if I stop taking it?

The weight comes back. In an extension of the main obesity trial, people were followed for a year after treatment stopped. They regained about two thirds of the weight they had lost. Blood pressure, blood fats and other markers drifted back toward where they started. The authors concluded that obesity behaves like a chronic condition, and that ongoing treatment is needed to hold on to the gains.

What are the real risks?

Gut symptoms are by far the most common. Nausea, vomiting and diarrhea hit a large share of users, mostly early on. In the big heart trial, 16.6 percent stopped the drug for side effects, against 8.2 percent on placebo. Gallstones and gallbladder inflammation are less common but serious. People with type 2 diabetes and existing eye damage had more retinopathy complications in one trial. The approved label also carries a boxed warning about thyroid tumors seen in rodents.

What should I ask a doctor before starting?

Ask whether you match the groups the trials actually studied. Ask about your personal and family history of medullary thyroid cancer, since the label rules that out. Mention any history of pancreatitis, gallstones or diabetic eye disease. Ask what monitoring you will get, and how long you would expect to stay on treatment. Then ask what the plan is if you stop, given the weight regain data.