Formic acid
The simplest carboxylic acid, containing a single carbon. Occurs naturally in various sources including the venom of bee and ant stings, and is a useful organic synthetic reagent. Principally used as a preservative and antibacterial agent in livestock feed. Induces severe metabolic acidosis and ocular injury in human subjects. — ChEBI
Safety documents & references
2 indexed referencesFind a product-specific SDS
Safety guides and government classification records are not a manufacturer’s SDS. Match supplier, product number, concentration, physical form, region and revision before using a document.
Identity & molecular properties
Source-linked values| CAS number | 64-18-6 | ChEBI ↗ |
| Molecular formula | CH2O2 | ChEBI ↗ |
| Molar mass | 46.025 g/mol | ChEBI ↗ |
| Monoisotopic mass | 46.00548 Da | ChEBI ↗ |
| Formal charge | 0 | ChEBI ↗ |
| ChEBI identifier | CHEBI:30751 | ChEBI ↗ |
Cross-source molecular data
PubChem| Molar mass | 46.025 g/mol | PubChem ↗ |
| Exact mass | 46.005479302 Da | PubChem ↗ |
| Computed XLogP | -0.2 | PubChem ↗ |
| Topological polar surface area (Ų) | 37.3 | PubChem ↗ |
| H-bond donors | 1 | PubChem ↗ |
| H-bond acceptors | 2 | PubChem ↗ |
| Rotatable bonds | 0 | PubChem ↗ |
PubChem computed values are shown separately from the ChEBI record. An exact InChIKey match was used to connect the records. Molecular descriptors do not describe a supplied product’s purity, particle size or performance.
Names & structural identifiers
Copy any identifierformic acidformic acidBDAGIHXWWSANSR-UHFFFAOYSA-N[H]C(=O)OInChI=1S/CH2O2/c2-1-3/h1H,(H,2,3)Classification & relationships
ChEBI ontologyRoles recorded in ChEBI
Database role annotations describe reported biological or chemical roles; they are not product approvals or recommendations for use.
Safety classification · Japan
NITE / Japanese governmentFormic acid · R04-C-053-JNIOSH, MOE
| Endpoint | Reported classification |
|---|---|
| Acute toxicity （Inhalation: Vapours） | Category 4 |
| Skin corrosion/irritation | Category 1 |
| Hazardous to the aquatic environment （Acute） | Category 3 |
Selected source-reported endpoints. Other endpoints, rationales and conditions remain in the original classification. Missing or unlisted information does not mean non-hazardous. This is not a global classification or transport decision.
Read the original NITE classificationMass ↔ amount of substance
Calculated from sourced massUses 46.025 g/mol from ChEBI. Assumes the substance described by this record; no purity or concentration correction is applied.
Elemental composition
Theoretical mass fractionsOCHCalculated theoretical mass fractions from the reported formula and PubChem periodic-table atomic masses. These are not assay or purity results.
Research & patent references
Selected source associationsSources & record history
Checked 27 Sep 2026Release 255, 9 September 2026. ChEBI three-star (manually annotated) source entry. View original record ↗ · CC BY 4.0
PubCAS formats source data, connects references and computes explicitly labelled conversions. CAS cross-references are supplied by ChEBI; they do not constitute CAS verification or endorsement.