Browse reference spectra from the USGS Spectral Library Version 7 and other curated sources. Each spectrum includes interactive plots, metadata, and downloadable data.
Have an unknown spectrum? Match it against this entire library with HQI similarity scoring — no install, no data leaves your machine.
Identify My SampleThis library contains real, measured reference spectra from open-access sources including the USGS Spectral Library Version 7, the Raman Open Database (ROD), FPbase fluorescent protein spectra, and additional curated datasets. Every spectrum is freely available with interactive plots, downloadable CSV and JCAMP-DX files, and detailed metadata — no account, no paywall.
Spectra cover multiple techniques: FTIR (infrared absorption and ATR), Raman, UV-Vis, NIR, and fluorescence. Materials span minerals, polymers, organic compounds, inorganic chemicals, soils, and biological samples. Use the search and filter controls below to browse by category, modality, or keyword — or match an unknown spectrum against the entire library using the Spectral Library Search tool.
Each reference spectrum page includes the full wavenumber or wavelength range, peak positions, sample metadata (source, instrument, preparation method where available), and links to related spectra in the same category. All data is sourced from peer-reviewed or government spectral databases under open licenses (CC0, CC BY, or U.S. government public domain).
Learn more about how spectral matching works, HQI scoring, and building a personal reference library on the Spectral Library Search page.
| Formula | Modality | Category | Source | ||
|---|---|---|---|---|---|
| Buspirone | C21H31N5O2 | Mass Spec | Chemical | MassBank | |
| But-3-enylglucosinolate | C11H19NO9S2 | Mass Spec | Chemical | MassBank | |
| Butacaine | C18H30N2O2 | Mass Spec | Chemical | MassBank | |
| Butachlor | C17H26ClNO2 | Mass Spec | Chemical | MassBank | |
| Butalbital | C11H16N2O3 | Mass Spec | Chemical | MassBank | |
| Butam | C15H23NO | Mass Spec | Environmental | MassBank | |
| Butamben | C11H15NO2 | Mass Spec | Chemical | MassBank | |
| Butane Camco frost 78K | — | FTIR | Organic | USGS | |
| Butane Camco frost 83K | — | NIR | Organic | USGS | |
| Butane-1,4-diyl bis(2-methylprop-2-enoate) | C12H18O4 | Mass Spec | Chemical | MassBank | |
| Butane-1-sulfonyl chloride | C4H9ClO2S | Mass Spec | Chemical | MassBank | |
| Butanoate | C4H8O2 | Mass Spec | Chemical | MassBank | |
| Butenafine | C23H27N | Mass Spec | Chemical | MassBank | |
| Butocarboxim | C7H14N2O2S | Mass Spec | Pesticide | MassBank | |
| Butocarboxim Sulfoxide | C7H14N2O3S | Mass Spec | Environmental | MassBank | |
| Butoconazole | C19H17Cl3N2S | Mass Spec | Chemical | MassBank | |
| Butoxycarboxim | C7H14N2O4S | Mass Spec | Environmental | MassBank | |
| Butralin | C14H21N3O4 | Mass Spec | Chemical | MassBank | |
| Buturon | C12H13ClN2O | Mass Spec | Environmental | MassBank | |
| Butyl 2,4-dichlorophenoxyacetate | C12H14Cl2O3 | Mass Spec | Pesticide | MassBank | |
| Butyl 2-ethylhexyl phthalate | C20H30O4 | Mass Spec | Chemical | MassBank | |
| Butyl Acetate | — | Raman | Pharmaceutical | Pharma Raman 2025 | |
| Butyl cyanoacetate | C7H11NO2 | Mass Spec | Chemical | MassBank | |
| Butyl diphenyl phosphate | C16H19O4P | Mass Spec | Natural product | MassBank | |
| Butyl methacrylate | C8H14O2 | Mass Spec | Chemical | MassBank | |
| Butyl myristate | C18H36O2 | Mass Spec | Chemical | MassBank | |
| Butyl pyridine-2-carboxylate | C10H13NO2 | Mass Spec | Chemical | MassBank | |
| Butyl stearate | C22H44O2 | Mass Spec | Chemical | MassBank | |
| Butyl-triphenylphosphonium | [C22H24P]+ | Mass Spec | Chemical | MassBank | |
| Butylamine | C4H11N | Mass Spec | Environmental | MassBank | |
| Butylisopropylamine | C7H17N | Mass Spec | Environmental | MassBank | |
| Butylparaben | C11H14O3 | Mass Spec | Chemical | MassBank | |
| Butylphosphonic acid | C4H11O3P | Mass Spec | Chemical | MassBank | |
| Butylphthalyl butylglycolate | C18H24O6 | Mass Spec | Chemical | MassBank | |
| Butyrolactone I | C24H24O7 | Mass Spec | Environmental | MassBank | |
| Butyrolactone II | C19H16O7 | Mass Spec | Environmental | MassBank | |
| Butyryl trihexyl citrate | C28H50O8 | Mass Spec | Environmental | MassBank | |
| Butyrylcarnitine | [C11H22NO4]+ | Mass Spec | Natural product | MassBank | |
| Bytownite | — | NIR | Mineral | USGS | |
| Bytownite | — | FTIR | Mineral | USGS | |
| C-desmethyl-metoprolol | C14H23NO3 | Mass Spec | Chemical | MassBank | |
| C.I. Acid Orange 10 | C16H12N2O7S2 | Mass Spec | Chemical | MassBank | |
| C.I. Acid Orange 24 | C20H18N4O5S | Mass Spec | Chemical | MassBank | |
| C.I. Acid Orange 3 | C18H14N4O7S | Mass Spec | Chemical | MassBank | |
| C.I. Acid Red 88 | C20H14N2O4S | Mass Spec | Chemical | MassBank | |
| C.I. Basic Red 9 | C19H17N3 | Mass Spec | Chemical | MassBank | |
| C.I. Direct Black 38 | C34H27N9O7S2 | Mass Spec | Chemical | MassBank | |
| C.I. Direct Red 81 | C29H21N5O8S2 | Mass Spec | Chemical | MassBank | |
| C.I. Direct Yellow 12 | C30H28N4O8S2 | Mass Spec | Chemical | MassBank | |
| C.I. Disperse Blue 27 | C22H16N2O7 | Mass Spec | Chemical | MassBank |