Varroa wash calculator — percent from a 300-bee sample
Alcohol wash or sugar roll: count the mites, divide by the bees, times 100. A half-cup of bees is about 300. The number only matters if you write it down. HiveFlow is where the count lives next to the treatment date.
Not veterinary advice. Threshold bands below follow public Honey Bee Health Coalition-style ranges used in US education (about 2–3% depending on season). Your state apiarist and current HBHC table win if they disagree.
A mite count that stays in a group chat is not IPM. The wash is a 10-minute field habit; the software job is keeping the percent next to the treatment so you can see whether the last oxalic or thymol actually moved the needle.
HiveSense will talk the inspection in if you bought that wedge. HiveFlow will not fake a BLE varroa sensor. We will store the number you counted in the alcohol jar and put a calendar reminder on the next wash.
- Shake ~300 bees (about 1/2 cup) from a brood frame into the wash jar.
- Run alcohol wash or sugar roll per your kit instructions.
- Count mites. Enter bees and mites here.
- Log the percent on the hive in HiveFlow. Treat from current HBHC / inspector guidance, not from this page alone.
Questions people type next to HiveFlow
- How do you calculate varroa infestation percent?
- Infestation % = (mites counted / bees in sample) × 100. A 9-mite drop from 300 bees is 3%. This calculator does that arithmetic.
- How many bees in an alcohol wash?
- US teaching default is about 300 bees, roughly a half-cup. Enter a different count if you weighed or counted the sample.