GLP-1 titration calculator

The calculator opens on the Wegovy injection preset. It reads each dose from the FDA label schedule and gives every step the label's four-week window:

• Step 1, weeks 1-4: 0.25 mg
• Step 2, weeks 5-8: 0.5 mg
• Step 3, weeks 9-12: 1 mg
• Step 4, weeks 13-16: 1.7 mg
• Step 5, week 17 onward: 2.4 mg

The summary reads 5 steps, a top dose of 2.4 mg, 16 weeks to the top dose, and 20 weeks charted. The 16 comes from four steps of four weeks before 2.4 mg begins. The last row says "onward" because 2.4 mg is the maintenance dose, held from week 17; the 20 weeks charted is only where the table stops drawing it. The label also lists an optional 7.2 mg "Wegovy HD" step for some patients after at least four weeks at 2.4 mg. It is not part of the standard escalation, so the table leaves it out and notes it below.

The custom fields start filled with a 0.25 mg start, a 0.25 mg step, 4 weeks per step and a 2.4 mg max. Type into any of them and the calculator switches to a custom build from those numbers. With the seed values it adds 0.25 mg every four weeks: 0.25, 0.5, 0.75, and so on up to 2.25 mg in weeks 33-36. The next step would be 2.5 mg, which is over the max, so it is clamped to 2.4 mg for weeks 37-40. That gives 10 steps, 36 weeks to the top dose and 40 total weeks. The gap between 16 and 36 weeks is why the presets copy the label's uneven steps rather than using a fixed increment.

A titration schedule is arithmetic on a calendar. Each step holds one dose for a number of weeks, and the next step starts the week after.

week start = 1 + weeks of all earlier steps
week end = week start + weeks per step - 1

In the custom builder the dose rises by the same increment each step and stops at the max. The final step is clamped down so it lands exactly on the max instead of overshooting it.

dose at step n = min(start + n x increment, max), for n = 0, 1, 2 ...

The summary figures come from the last row. "Weeks to top dose" is the week the last step starts, minus one. "Total weeks" (or "weeks charted" on a preset) is the week the last step ends.

A few edge cases follow from the code. An increment of 0 gives a single flat step. The start dose must be above zero and no higher than the max, and weeks per step must be a whole number, or the calculator asks you to fix the inputs instead of drawing a table. Doses are rounded to six decimal places to clear floating-point noise and shown with up to three, and a build stops at 500 steps so a tiny increment cannot run forever.

The label presets skip the increment formula. Their doses are read from the label schedules on our reference pages and laid out step by step, which is how semaglutide's 1 to 1.7 to 2.4 mg jumps render without distortion. This is schedule math and a reference layout, not a recommendation to take any dose.