Tirzepatide & GLP-1 Dose Calculator

About

Three GLP-1 dosing tools in one popup — pick the one that matches your medication, get an answer in seconds. The same calculators trusted on glapp.io/tools, rebuilt for your browser toolbar: no tabs to open, no hunting for a bookmarked chart on injection day.

VIAL DOSE CALCULATOR (mg → units)
Enter your prescribed dose in mg and the concentration printed on your vial label (mg/mL or mg/0.5 mL). Get the exact units to draw on a standard U-100 insulin syringe, with a visual syringe to double-check the markings. Works with compounded tirzepatide, semaglutide, and other GLP-1 medications in vials.

MOUNJARO PEN CLICKS
Select your KwikPen strength (2.5–15 mg) and your desired dose, and get the number of clicks to dial — a click counter that replaces a printed click chart. Also shows the injection volume, how much remains in the pen, how many weeks it will last at your injection frequency, and price per injection if you enter what you paid. Supports the "Golden Dose" priming-fluid option.

REVERSE CALCULATOR (units → mg)
Already injected, or double-checking a draw? Convert syringe units back to milligrams using your vial concentration — see the actual dose delivered, plus the volume injected.

WHO IT'S FOR
• You inject from vials (brand-name or compounded from a telehealth pharmacy) and draw with an insulin syringe
• You titrate or split doses on a KwikPen and count clicks instead of dialing the full dose
• You log your injections and want to confirm the exact amount a past draw delivered
• Caregivers and nurses who double-check a draw before injection day

EXTRAS
• Remembers the tool and inputs you used last, so weekly recalculations take seconds
• Handles both mg/mL and mg/0.5 mL label formats — no manual conversion
• Sanity checks catch implausible entries, like a draw beyond syringe capacity
• Light and dark mode follow your system setting
• Works completely offline — nothing to sign up for

FREQUENTLY ASKED QUESTIONS

How many units is 2.5 mg?
It depends on your vial's concentration. At 10 mg/mL, 2.5 mg is 25 units; at 20 mg/mL it's 12.5. Enter your own label values to get the exact number.

How many clicks is 5 mg on a 10 mg pen?
30 clicks. Each KwikPen holds its full strength in 0.6 mL and one click equals 0.01 mL — the calculator does this math for any strength and any partial amount.

What syringe does the calculator assume?
A standard U-100 insulin syringe, where 100 units equal 1 mL — the type used for virtually all GLP-1 vial injections.

My vial label says mg/0.5 mL — do I need to convert?
No. Flip the unit toggle and enter the number exactly as printed; the calculator handles the conversion.

Does it work with compounded medication from a telehealth pharmacy?
Yes. As long as the concentration is on the label, the math is identical for brand-name and compounded formulations.

Why does my result differ from a printed click chart?
Most charts are rounded or assume one specific strength. The calculator computes your exact dial count from the actual strength and your prescribed amount.

THE MATH
All conversions use standard pharmaceutical formulas on the U-100 standard (100 units = 1 mL); pen concentration is strength ÷ 0.6 mL. The formulas follow FDA-published dosing references, and every calculation path is covered by automated tests.

PRIVACY
No data collection, no account, no network requests, zero browser permissions. Your inputs are saved on your device only.

DISCLAIMER
This extension is for informational purposes only and is not medical advice. Always verify dosing with your healthcare provider or pharmacist before injecting. Mounjaro and Zepbound are registered trademarks of Eli Lilly and Company; this extension is not affiliated with or endorsed by Eli Lilly.

ABOUT GLAPP
Made by the team behind Glapp (glapp.io), the first GLP-1 tracker built for better weight loss. More free tools — dose plotters, titration planners, cost calculators — at glapp.io/tools.