Enter particle counts to get the ISO 4406 code X/Y/Z
| Size | Entered Count | Per mL | Code | Upper Limit (per mL) |
|---|---|---|---|---|
| >4 µm(c) | - | - | - | - |
| >6 µm(c) | - | - | - | - |
| >14 µm(c) | - | - | - | - |
For fluid power engineers who pull raw particle counts off a bottle sample or an inline counter and need to state them as an ISO 4406 code without hand-reading the scale table or mis-stepping it with a log2 shortcut.
This converter precisely translates raw >4 µm(c), >6 µm(c), and >14 µm(c) particle counts into an ISO 4406 cleanliness code X/Y/Z. It uses the standard's rounded scale limits, which range from 0.01 to 2,500,000 particles per mL, ensuring accuracy for reporting fluid cleanliness. This tool is for preliminary estimation only, not a substitute for review by a qualified/licensed engineer.
Q: How do I convert a particle count per 100 mL into an ISO 4406 code?
A: Set the unit dropdown to "counts are per 100 mL"; the tool divides each count by 100 to get particles per mL and then looks that value up on the scale, so 13,000 per 100 mL is treated as 130 per mL.
Q: Why does a log2 calculation give a different ISO 4406 code?
A: The scale limits are rounded rather than exact powers of two — 1.3, 2.5, 1300 and 2500 sit where doubling would put 1.28, 2.56, 1280 and 2560 — so log2 lands on the wrong band; this tool takes the smallest code whose upper limit is greater than or equal to the per-mL count, so 1.29 per mL gives 7, 2.6 gives 9, 100 gives 14 and 1301 gives 18.
Q: What does an ISO code of >28 mean?
A: The scale runs from code 0 at 0.01 particles per mL up to code 28 at 2,500,000 particles per mL; any count above 2,500,000 per mL falls off the top of that table and is reported as ">28" rather than a number.
Q: What do the three numbers in the code X/Y/Z stand for?
A: They are the individual codes for the >4 µm(c), >6 µm(c) and >14 µm(c) counts, in that order, so the first number always comes from the >4 µm(c) field and the last from the >14 µm(c) field.