On entomologist Justin O. Schmidt’s sting pain scale — built from decades of the researcher deliberately letting stinging insects sting him and rating the result — an ordinary honeybee sting lands at a 2, squarely in the middle of a scale that actually runs from 0 to 4, not 1 to 4 as it’s often simplified. The Schmidt Sting Pain Index has become the default reference point for comparing insect stings precisely because it isn’t just a number: every rating comes with Schmidt’s own vivid, specific description of what the pain actually feels like, and the honeybee’s entry is one of the more quoted of the bunch.
Key Takeaways
- The Schmidt Sting Pain Index was developed by entomologist Justin O. Schmidt (1947-2023), who worked for years at the USDA’s Carl Hayden Bee Research Center in Tucson, Arizona, starting with a 1983 paper and expanding it through a 1990 study covering 78 species.
- The full scale actually runs from 0 (a sting too weak to break human skin) to 4 (severe); the Western honey bee’s sting is rated a 2, the same tier as a typical yellowjacket sting; paper wasps rate 2 to 3, and most Polistes species Schmidt tested rate 3.
- Only the bullet ant and the tarantula hawk wasp were originally rated a full 4 — the most severe category on the scale.
- A separate 2014 peer-reviewed study used honeybee stings specifically to map how pain varies by body location, finding roughly a 4-point spread on its own 1-10 scale between the least painful site (the skull, 2.3) and the most painful (the nostril, 9.0).
- Each rating comes with a specific, often vivid written description from Schmidt rather than just a number, which is a large part of why the index is so widely quoted outside entomology circles.
Table of Contents
- The Scale, With Schmidt’s Own Descriptions
- Where the Honeybee Actually Ranks
- How Sting Location Changes the Pain
- How Schmidt Built the Scale
- Why a Pain Scale Needs Descriptions, Not Just Numbers
- Frequently Asked Questions
The Scale, With Schmidt’s Own Descriptions
| Level | Insect | Schmidt’s description |
|---|---|---|
| 1 | Sweat bee (Lasioglossum spp.) | “Light and ephemeral, almost fruity. A tiny spark has singed a single hair on your arm.” |
| 1.2 | Fire ant (Solenopsis invicta) | “Sharp, sudden, mildly alarming. Like walking across a shag carpet and reaching for the light switch.” |
| 2 | Western honey bee (Apis mellifera) | “Burning, corrosive, but you can handle it. A flaming match head lands on your arm and is quenched first with lye and then sulfuric acid.” |
| 2 | Yellowjacket (Vespula spp.) | “Hot and smoky, almost irreverent. Imagine W. C. Fields extinguishing a cigar on your tongue.” |
| 2 | Paper wasp (Polistes spp.) | “Burning, throbbing, and lonely. A single drop of superheated frying oil landed on your arm.” |
| 3 | Red paper wasp (Polistes canadensis) | “Caustic and burning, with a distinctly bitter aftertaste. Like spilling a beaker of hydrochloric acid on a paper cut.” |
| 4 | Bullet ant (Paraponera clavata) | “Pure, intense, brilliant pain. Like walking over flaming charcoal with a 3-inch nail embedded in your heel.” |
| 4 | Tarantula hawk (Pepsis spp.) | “Blinding, fierce, shockingly electric. A running hair dryer has just been dropped into your bubble bath.” |
Where the Honeybee Actually Ranks
“Burning, corrosive, but you can handle it. A flaming match head lands on your arm and is quenched first with lye and then sulfuric acid.”
A honeybee sting’s rating of 2 puts it in genuinely unremarkable company — the same tier as a yellowjacket and some paper wasps (most Polistes species rate a notch higher, at 3), insects most people already treat as an everyday, if unpleasant, backyard hazard rather than something to fear seriously. That’s a useful data point precisely because the honeybee sting functions as most people’s mental reference point for “normal sting pain” — it’s what a huge share of Schmidt’s readers have personally experienced, which makes it the natural anchor for understanding every other rating on the scale relative to something concrete. It was, in fact, deliberately used that way: Schmidt built the honeybee sting into the scale as an internal reference point, the fixed “2” that every other species’ rating gets calibrated against.
It’s also worth separating pain from danger. Schmidt’s scale measures the intensity of the pain response in a person without a venom allergy, not medical risk — a honeybee sting rated a 2 for pain can still be genuinely dangerous, even fatal, for the small percentage of people with a severe bee venom allergy — see this site’s breakdown of local versus systemic sting reactions for how to tell the difference — a distinction the pain index was never designed to capture.
How Sting Location Changes the Pain
The Schmidt Index compares different species using one honeybee sting as the standard, but it says nothing about how much a single honeybee sting’s pain can vary depending on where on the body it lands. A 2014 study published in the peer-reviewed journal PeerJ addressed exactly that gap: the author, biologist Michael L. Smith, had himself stung by honeybees on 25 different body locations, three times each, and rated each sting’s pain on a 1-10 scale relative to the forearm as an internal standard.
| Body location | Average pain rating (1-10) |
|---|---|
| Skull | 2.3 |
| Upper arm | 2.3 |
| Forearm (the study’s reference point) | 5.0 |
| Top of the hand | 5.3 |
| Palm | 7.0 |
| Upper lip | 8.7 |
| Nostril | 9.0 |
The three least painful sites overall were the skull, the middle toe tip, and the upper arm; the three most painful were the nostril, the upper lip, and the penis shaft. Sting location turned out to be a statistically significant predictor of pain intensity, while which side of the body was stung, and which of the three testing rounds it happened in, were not — suggesting the pattern reflects genuine differences in nerve density and skin sensitivity across body regions rather than noise or desensitization. It’s a genuinely useful, if unusual, companion data point to the main Schmidt Index: where a honeybee stings you changes the experience roughly as much as which insect stings you does.
How Schmidt Built the Scale
Justin O. Schmidt, an entomologist who spent years working at the USDA’s Carl Hayden Bee Research Center in Tucson, Arizona, first published a version of the pain index in 1983 as a way to systematically compare the properties of different insect venoms rather than simply as a novelty ranking. He expanded it substantially in a 1990 paper classifying stings from 78 species across 41 genera of Hymenoptera, refining both the numeric ratings and his written descriptions as he accumulated more direct experience — largely by allowing himself to be stung by the insects he was studying, a research method that became a defining, somewhat notorious part of his professional reputation. He continued developing the work for decades, culminating in a full book, The Sting of the Wild, published in 2016. Schmidt died in Tucson in February 2023, at age 75, from complications of Parkinson’s disease, having been stung an estimated 1,000-plus times over the course of his career in the name of the research.
Why a Pain Scale Needs Descriptions, Not Just Numbers
A purely numeric scale — this sting is a 2, that one’s a 4 — would tell you relative intensity but nothing about what the pain actually feels like, and Schmidt’s decision to pair every rating with a specific, often strikingly written description is exactly what turned a niche entomological measurement tool into something quoted in outlets well outside science journalism. “A flaming match head lands on your arm and is quenched first with lye and then sulfuric acid” communicates something a bare number 2 simply can’t: not just how bad it is, but the specific character and duration of the sensation, in a way that lets two very different stings both rated a “2” still read as recognizably distinct experiences.
That combination of scientific rigor and genuinely memorable writing is the real reason the Schmidt Sting Pain Index has outlived plenty of more rigorously statistical pain-measurement attempts — it’s useful to researchers and quotable enough that ordinary readers, well outside entomology, still repeat it decades later. The Natural History Museum in London keeps its own public-facing rundown of the index, a sign of how far the scale traveled beyond the entomology journals it started in.
For how a honey bee sting compares with a wasp sting in practice, see bee sting vs wasp sting.
For a bee at the bottom of the scale, see where sweat bees rank on Schmidt's scale.
Frequently Asked Questions
What is the highest rating on the Schmidt Sting Pain Index?
The scale runs from 0 to 4; in Schmidt’s original published work, only the bullet ant was given a full rating of 4, with the tarantula hawk wasp later added at the same top level.
Does the scale really start at 0, not 1?
Yes, technically. Schmidt’s original 1990 classification defines 0 as a sting that cannot even penetrate human skin, though many popular summaries of the index (including some museum write-ups) simplify it to a 1-to-4 range because the commonly cited examples all fall within that range.
Does a lower Schmidt Index rating mean a sting is safer?
Not necessarily. The index measures how much a sting hurts, not how medically dangerous it is — a low-rated sting from an insect like a honeybee can still be dangerous or fatal for someone with a genuine venom allergy, regardless of its pain ranking.
Who was Justin Schmidt?
Justin O. Schmidt (1947-2023) was an American entomologist who worked at the USDA’s Carl Hayden Bee Research Center and is best known for developing and refining the sting pain index that carries his name, culminating in his 2016 book The Sting of the Wild. He died in February 2023 at age 75.
How did Schmidt determine the ratings?
Largely through direct personal experience — Schmidt was stung, often deliberately, by dozens of species of bees, wasps, and ants over the course of his research, using his own reactions to compare and calibrate the relative pain of each species’ sting.
Does where a honeybee stings you actually change how much it hurts?
Yes, significantly. A 2014 self-experiment published in PeerJ found honeybee sting pain ranged from an average of 2.3 (on the skull or upper arm) to 9.0 (on the nostril) on a 1-10 scale, using the forearm as the reference point.
