Spectral File Viewer

Research labs, teaching environments, and QA teams regularly deal with spectral data files locked inside proprietary formats. Without the right vendor software — which is often expensive and platform-specific — simply viewing a spectrum can be a roadblock. SpectralBench removes that barrier with a free online spectrum viewer that runs entirely in your browser.

Drag any JCAMP-DX, SPC, Bruker OPUS, or CSV file onto the workbench and get an interactive chart in seconds. SpectralBench parses the file on your machine — nothing is ever uploaded to a server — so your data stays private. Whether you need to quickly inspect an FTIR absorption spectrum, view JCAMP-DX files online, or explore the metadata embedded in a legacy SPC file, the viewer gives you the tools you need without the overhead.

How It Works

Getting started takes seconds: drag and drop any spectral file onto the viewer, or click the upload area to browse your files. SpectralBench automatically detects the file format — whether it is JCAMP-DX, SPC, Bruker OPUS, CSV, or plain text — and parses it entirely client-side. No plugins, no downloads, no server round-trips.

Once parsed, an interactive chart renders your spectrum with wavenumber or wavelength on the x-axis and absorbance or transmittance on the y-axis. Use the crosshair tool to read exact values at any point, zoom into regions of interest with click-and-drag, or toggle the peak detection overlay to automatically label absorption bands and valleys.

For deeper inspection, switch to the annotated view to see the raw file source with inline documentation explaining every header field, data block, and metadata tag. This is especially valuable when troubleshooting file compatibility issues or verifying that instrument parameters were recorded correctly. When you are ready to share or reprocess your data, use the Spectral File Converter to export to CSV for further analysis in Excel or Origin.

Supported File Formats Explained

JCAMP-DX (.jdx, .dx) — The IUPAC/JCAMP standard for spectroscopic data exchange. Widely used in academic research and open-access spectral databases, JCAMP-DX is text-based and self-describing. Despite being an open standard, many tools do not support its full specification, including compressed data formats and multi-block files. SpectralBench handles the complete JCAMP-DX specification so you can view JCAMP-DX files online without worrying about compatibility.

SPC (.spc) — The Thermo/Galactic GRAMS binary format, common in analytical labs running Thermo Fisher instruments. SPC files store single or multiple spectra with rich metadata, but opening them typically requires GRAMS or compatible commercial software. SpectralBench reads the full SPC binary structure including old and new format variants — a free alternative to open SPC spectral files in your browser.

Bruker OPUS (.0, .1, .2, ...) — The proprietary binary format from Bruker FTIR spectrometers. Numbered file extensions make OPUS files unrecognizable to most operating systems and software. Viewing them usually requires Bruker's OPUS software, which is expensive and Windows-only. SpectralBench lets you view Bruker OPUS files online from any platform at no cost.

CSV / TXT — Universal tabular formats that are easy to work with but lack embedded metadata. SpectralBench auto-detects the delimiter and column layout, so you can view spectral data exported from virtually any instrument or software package. For more structured output, use the converter to produce a JCAMP-DX file with proper metadata.