Science
SHU / Capsaicin Converter
Convert between Scoville Heat Units and capsaicin concentration instantly. Type a value into any field and the others update in real time. All conversions use the standard ASTA factor: 1 ppm of capsaicin equals 16.1 SHU.
Converter
Enter a value in any field. The remaining fields calculate automatically.
Conversion Formulas
- SHU = ppm × 16.1
- ppm = SHU ÷ 16.1
- mg/g = ppm ÷ 1,000
- % = ppm ÷ 10,000
The factor 16.1 comes from the American Spice Trade Association (ASTA) standardization. When HPLC measures capsaicinoid concentration in parts per million, that value is multiplied by 16.1 to yield the equivalent SHU figure. The factor accounts for the molar pungency of capsaicin relative to the original organoleptic dilution method.
The other unit conversions are straightforward metric relationships. Since ppm means parts per million by mass, 1,000 ppm equals 1 mg/g (one milligram of capsaicin per gram of dried pepper). Similarly, 10,000 ppm equals 1% by mass. These units appear in pharmaceutical research, food chemistry publications, and regulatory documents depending on the field and jurisdiction.
Reference Points
Use these reference values to calibrate your intuition. Each row shows a familiar pepper or benchmark alongside its SHU, ppm, mg/g, and percent capsaicin values. Values are approximate midpoints for natural peppers and HPLC-verified figures for Scoville Splice specimens.
| Pepper | SHU | ppm | mg/g | % |
|---|---|---|---|---|
| Jalapeño | 8,000 | 496.89 | 0.4969 | 0.0497 |
| Habanero | 350,000 | 21,739.13 | 21.74 | 2.17 |
| Ghost Pepper | 1.04M | 64,684.91 | 64.68 | 6.47 |
| Carolina Reaper | 2.20M | 136,645.96 | 136.65 | 13.66 |
| Pepper X | 2.69M | 167,080.75 | 167.08 | 16.71 |
| SS Verbal Warning | 3M | 186,335.4 | 186.34 | 18.63 |
| SS D.N.R. | 13M | 807,453.42 | 807.45 | 80.75 |
| Pure Capsaicin | 16M | 993,788.82 | 993.79 | 99.38 |
Why Multiple Units Exist
SHU is the consumer-facing unit, rooted in the original 1912 dilution method and preserved by regulatory inertia and brand recognition. Parts per million (ppm) is the native output of HPLC analysis and the standard in analytical chemistry publications. Milligrams per gram (mg/g) and percent are simply rescaled versions of ppm used in pharmaceutical and food-science contexts. Capsaicin patch labels, for instance, specify concentration as a percentage (the standard prescription patch is 8% capsaicin, equivalent to 80 mg/g or 80,000 ppm or roughly 1,288,000 SHU).
At the top of the Scoville Splice lineup, D.N.R. at 13 million SHU translates to approximately 807,453 ppm, or 807 mg/g, or 80.7% capsaicinoid concentration. That is 81% of the way to pure crystalline capsaicin. No natural pepper comes close: Pepper X tops out around 167,081 ppm (2.69 million SHU), which is roughly 16.7% capsaicinoid concentration. The gap between natural breeding and computational genomic engineering shows up starkly in every unit.