Parts per million
ppmcx:ppm · Ratio
1 ppm = 0.000001 1.
- Quantity kind
- Ratio
- SI dimension
1- Allowed roles
- Scalar
- Unit system / convention
- Other conventions
- Registry code
ppm
Scope and distinctions
Ratio scale only. A concentration must additionally declare mass/mass, volume/volume, mole fraction or other appropriate basis.
Available operations
UUCE executable Preview · Use cx:ppm with a compatible unit and a pinned snapshot.
No legacy converter is linked for this definition.
Verification scope
- UUCE conversion capability
units.convertversion0.1.1· VERIFIED- Production binding at publication
- CURRENT
The definition lifecycle describes this registry entry. CVP status describes the conversion capability and the cases and rejection partitions in its Manifest. CVP Manifest · Public replay cases
Candidate is a registry lifecycle state. It is not a completed review or CVP verification.
Definition sources
- BIPM — The International System of Units (SI)
9th edition, version 4.01, June 2026
Section 5.4.7: ratio quantities and ppm = 1e-6
Source checked:Definition metadata attributed to BIPM; brochure licensed CC BY 4.0.
Definition and registry versions
- Definition revision
- 1.0.0
- Registry snapshot
- 0.3.0-preview.3 · preview
- Definition lifecycle
- candidate
- Definition owner
- core.metrology
- Definition digest
1983c1456c8233b99e85c883626c8fc0ff947879b215f4ed4319e013f3b1647b- Definition dependency digest
a0c9eb8b9e3eceb6ef8230e1dd5e24da3424791639ec060bd6b75d0f3cf47b9d
Digests identify definition content; they are not CVP evidence or production attestations.