Supply Runway Calculator

Enter what you have on hand and your dosing schedule to see how long it lasts, see how titrating the dose changes it, and export the math.

Used to label the results and your Excel / Sheets export.
What are you tracking?
How much do you have on hand?

On hand: 10 mg

Dose per administration
Amount taken each time you dose.
How often do you dose?
Starting from
Used to estimate your run-out date.
– days of supply

 

Check your inputs:
Total doses –
Weekly use –
Runs out –

If you titrate the dose

How long the same stockpile lasts at different doses, keeping your current schedule. Your current dose is highlighted.

Dose Weekly use Total doses Runway Runs out

How long will my supply last?

What "runway" means here

Runway is simply how long your current stockpile lasts before you run out, at the schedule you actually dose on. The calculator turns the amount on hand into a number of doses, then stretches those doses across the calendar based on how often you take them.

total doses = amount on hand ÷ dose per administration
runway (days) = total doses ÷ doses per week × 7

Worked example

A 10 mg peptide vial dosed at 250 mcg (0.25 mg) once daily gives 10 ÷ 0.25 = 40 doses. At 7 doses per week that is 40 ÷ 7 × 7 = 40 days of supply. Drop to every other day (3.5 doses per week) and the same vial stretches to about 80 days.

Peptides, oils, and orals

For peptides, the stockpile is the total mass across your vials (vials × mg per vial) and the dose is in mcg or mg. For oils, the stockpile is the total drug mass (bottles × mL × mg/mL concentration) and the dose is in mg. For orals, the stockpile is the number of tablets or capsules and the dose is how many you take each time.

Titrating the dose

Most people keep the same dosing schedule and adjust the dose up or down. A larger dose empties the stockpile faster, a smaller dose stretches it further. The comparison table holds your schedule fixed and shows the runway at a range of doses around your current one, so you can see how a titration changes how long your supply lasts before you commit to it.

Exporting to Excel or Google Sheets

Download Excel produces a formatted .xlsx file: a branded header, highlighted editable input cells, and a styled comparison table, with every result written as a live formula so you can keep adjusting the numbers in your own spreadsheet. Copy for Google Sheets puts the same formula-backed table on your clipboard. Open a Google Sheet, click cell A1, and paste. The formulas reference the input cells, so changing the amount on hand or the dose recalculates the whole sheet. Pasting keeps the formulas but not the colours; for the fully styled version in Google Sheets, use Download Excel then File → Import the file, which preserves both the formatting and the live formulas.

Accuracy notes

Results assume each dose draws the full amount you entered and ignores residual loss in the vial, syringe dead space, and rounding at the syringe. "Every other day" is treated as 3.5 doses per week for a smooth average. Run-out dates are estimates based on average weekly use, not a literal day-by-day calendar.

Data handling and privacy

Everything runs in your browser. Nothing is uploaded. A share link encodes your inputs in the URL only when you choose to generate one.

Scope & safety

PepRecon is a research and education resource. This calculator and reference material are provided for informational purposes and are not medical advice; they do not establish a dosing recommendation. Consult a qualified clinician before use.

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