Cannabis Learning Center

THC % vs Milligrams

Convert THC percentage and weight into approximate milligrams.

THC % to milligrams calculator

This calculator compares cannabis percentage to milligrams. It is label math only, not dosing advice.

mg THC = (THC % ÷ 100) × grams × 1000

THCa conversion calculator

Use this for labels that list THCa and delta-9 THC separately.

Estimated total THC ≈ Δ9 THC + (THCa × 0.877)

Example conversions

Product mathResult
1 g at 20%About 200 mg total THC before losses.
0.5 g at 28%About 140 mg total THC before losses.
0.25 g at 30%About 75 mg total THC before losses.
10 mg edibleAlready listed as amount, not percentage.

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