Compound Lookup.
Compound Lookup
Look up agronomic compounds by CAS, formula, name, or InChI Key. Authoritative data from PubChem (NIH/NLM).
What this lookup does
This tool queries the PubChem REST API — the National Center for Biotechnology Information's open chemistry database — and returns structured information about any compound you search.
For agronomic compounds (fertilizer ingredients, pesticide active ingredients, biostimulants, soil amendments, pH adjusters), this gives you authoritative chemistry: molecular formula, molecular weight, IUPAC name, common synonyms, and links to safety data and chemical structure.
This is the same data source OAT's full Chemistry Engine uses to populate its compound catalog. The lookup is also what auto-fills compound details when you add a new fertilizer ingredient or pesticide to the OAT Manage tier — type a CAS number, get the chemistry filled in.
Common agronomic compounds and their CAS numbers
| Compound | CAS | Formula | Use |
|---|---|---|---|
| Potassium nitrate | 7757-79-1 | KNO₃ | K + N source |
| Calcium nitrate (tetrahydrate) | 10124-37-5 | Ca(NO₃)₂·4H₂O | Ca + N source |
| Ammonium nitrate | 6484-52-2 | NH₄NO₃ | N source (regulated) |
| Urea | 57-13-6 | (NH₂)₂CO | Slow-release N |
| Magnesium sulfate (Epsom salt) | 7487-88-9 | MgSO₄ | Mg + S source |
| Monopotassium phosphate (MKP) | 7778-77-0 | KH₂PO₄ | P + K source |
| Calcium chloride | 10043-52-4 | CaCl₂ | Foliar Ca |
| Iron EDTA | 15708-41-5 | FeC₁₀H₁₂N₂O₈ | Chelated Fe |
| Boric acid | 10043-35-3 | H₃BO₃ | B source |
| Zinc sulfate | 7733-02-0 | ZnSO₄ | Zn source |
| Copper sulfate | 7758-99-8 | CuSO₄ | Cu source / fungicide |
| Phosphoric acid | 7664-38-2 | H₃PO₄ | pH down + P |
| Potassium hydroxide (KOH) | 1310-58-3 | KOH | pH up |
| Pyrethrins | 8003-34-7 | varies | Pesticide (organic) |
| Azadirachtin (neem) | 11141-17-6 | C₃₅H₄₄O₁₆ | Pesticide (organic) |
| Spinosad | 168316-95-8 | varies | Pesticide (OMRI-listed) |
| Salicylic acid | 69-72-7 | C₇H₆O₃ | Plant immune signaling |
| Humic acid | 1415-93-6 | varies | Biostimulant |
Why CAS numbers matter
The CAS Registry Number is a unique identifier assigned by Chemical Abstracts Service to every chemical compound. Two products labeled "calcium nitrate" might have the same CAS number (10124-37-5 for the tetrahydrate hydrate) — confirming they're chemically equivalent regardless of brand.
For organic certification (NOP, OMRI), the National List approves or restricts substances by CAS number. Knowing the CAS of an ingredient is the only definitive way to verify NOP-allowed status. The lookup above gives you the CAS; you can then cross-reference the OMRI Listed database or the USDA NOP National List of Allowed and Prohibited Substances.
Compound data from PubChem (NIH/NLM, public domain). Free under CC BY 4.0 for the OAT widget itself. Cite as "OAT Compound Lookup (openagriculturetechnology.com)".