DoseMarks
FDA-approved (brand)GLP-1 receptor agonist

Semaglutide Dosage Calculator

Injectable semaglutide is a once-weekly GLP-1 medication. For a ready-mixed vial, use the concentration on your pharmacy label, without adding water. This calculator converts an entered injection dose; it does not apply to semaglutide tablets.

Example vial inputs
2 mg · 5 mg · 10 mg
Dosing frequency
Once weekly
Half-life
About 1 week

FDA-approved as Ozempic® and Wegovy®. Compounded vials are not FDA-approved.

Step 1

Your vial & dose

U-100 syringes

What’s in your vial?

Vial values are examples. Replace them with your product or pharmacy label values.

Copy the concentration (mg/mL) from your pharmacy label. Don’t add water to a vial that is already liquid.

mg/mL
mL

Step 2

mg

Doses on the FDA label

Step 3

Syringe size

Smaller barrels have finer marks, which makes small doses easier to read.

Live syringe preview · 100-unit

010203040506070809010010u

Draw to

10 units

= 0.1 mL of liquid

Concentration
2.5 mg/mL
Each unit contains
25 mcg
Your dose
250 mcg
Doses per vial
20
Show the math
  1. Concentration = 2.5 mg/mL (from your label)
  2. Volume = 0.25 mg ÷ 2.5 mg/mL = 0.1 mL
  3. Units = mL × 100 = 10 units

Dosing schedule

Wegovy® injection label — adult weight management

This table covers adult weight management with Wegovy injections, not Ozempic, oral semaglutide or other indications. Escalation may be delayed by 4 weeks if a dose is not tolerated. Maintenance may be 1.7 or 2.4 mg weekly (2.4 mg is recommended by the label), selected for response and tolerability. The optional 7.2 mg dose is only for adults who tolerate 2.4 mg for at least 4 weeks and clinically need further weight reduction. A brand schedule does not prescribe a compounded product’s dose.

  1. Weeks 1–4

    250 mcg

    Starting dose

  2. Weeks 5–8, if tolerated

    500 mcg

    Escalation

  3. Weeks 9–12, if tolerated

    1 mg

    Escalation

  4. Weeks 13–16; may continue

    1.7 mg

    Also a maintenance option

  5. Week 17 onward, if selected

    2.4 mg

    Recommended maintenance

  6. ≥ 4 weeks at 2.4 mg, if needed

    7.2 mg

    Optional adult weight-management dose

Dashed = conditional step. Your prescriber selects the dose for your indication, response and tolerability.

Arithmetic at your entered concentration: 2.5 mg/mL, 100-unit syringe. Follow the prescribed product’s device instructions; this is not a pen conversion.

Wegovy® injection label — adult weight management
WhenWeekly doseVolumeDraw toNote
Weeks 1–4250 mcg0.1 mL10 unitsStarting dose← your dose
Weeks 5–8, if tolerated500 mcg0.2 mL20 unitsEscalation
Weeks 9–12, if tolerated1 mg0.4 mL40 unitsEscalation
Weeks 13–16; may continue1.7 mg0.68 mL68 unitsAlso a maintenance option
Week 17 onward, if selected2.4 mg0.96 mL96 unitsRecommended maintenance
≥ 4 weeks at 2.4 mg, if needed7.2 mg2.88 mL288 unitsOptional adult weight-management dose

Exceeds entered vial amount

Exceeds syringe capacity — confirm with pharmacist

Before reconstitution

Five checks for a powder vial

For powder (freeze-dried) vials only. If your vial arrived as a liquid, it is already mixed — never add water to it; use the concentration on the label. Approved injectable brands are supplied as solutions. This guide applies only if a pharmacy has specifically supplied powder with preparation instructions; it does not apply to pens or ready-mixed vials.

  1. 01

    Check the product

    Confirm that you have a powder intended for preparation and the instructions for that exact product. Ask your pharmacist if anything is unclear.

  2. 02

    Confirm the diluent

    Use only the diluent and volume specified in those instructions. The calculator cannot determine whether a diluent or mixing volume is suitable.

  3. 03

    Follow the instructions

    Follow the product’s preparation method and the technique your pharmacist taught you. These checks are not a substitute for its Instructions for Use.

  4. 04

    Verify concentration

    Use the labeled concentration after preparation, or the total drug amount and final solution volume. The final volume may differ from the amount of diluent added.

  5. 05

    Check storage & discard

    Follow the product’s storage conditions and discard time. Some preparations require immediate use. Do not infer a storage period from the calculator.

Storing your vial

  • For an approved brand, follow the storage and discard instructions for your exact presentation; pen, single-dose vial and multi-dose vial instructions can differ.
  • For compounded GLP-1 vials, follow the pharmacy’s temperature instructions and any earlier discard date. FDA recommends discarding multi-dose compounded GLP-1 vials within 28 days of first use, even if the compounder gives a longer period.

Please read before injecting

Always confirm your dose, concentration and syringe markings with your prescriber or pharmacist. Small calculation errors can have serious consequences. This tool does math — it doesn’t tell you what dose to take.

Sources

References

Last updated October 2026.

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