About InjectBuddy
Built and maintained by Sam Calder.
Built and maintained by Sam Calder, a software developer, not a medical professional. InjectBuddy performs standard volume and ratio calculations based on your inputs. These calculators do not constitute medical advice — always verify dosing with your prescribing doctor or pharmacist.
Why this exists
Calculating the exact volume to draw from a vial is simple arithmetic (dose ÷ concentration = volume), but most calculator pages were cluttered, ad-heavy, or required accounts. So InjectBuddy was built, then the peptide, BMI and free testosterone index calculators.
Every calculator does standard arithmetic on numbers you already have from your doctor, prescriber, pharmacist, or blood panel. Nothing more. They run in your browser with no login and no ads; an account is optional (see our Privacy Policy). It is not a medical service.
Who builds this
I’m the person accountable for the maths on this site. Every formula is standard arithmetic, verified against reference formulas and independent calculators, with the working shown on each page. If a number is ever wrong, it’s on me to fix it — email hello@injectbuddy.com and I will, promptly.