View JDX files in your browser
How spectrometers and the NIST WebBook hand out spectra. Open a JCAMP-DX right here, drawn as chemists read it, with nothing to install. Nothing leaves your device.
Or drop it anywhere on this page
What you'll see
Your spectrum opens drawn on paper the way chemists read it, with its peaks labeled.
- IR, Raman, UV, NMR and mass spectra • Wavenumbers and ppm right to left
- Peaks labeled • Peaks hides them
- Read the curve • Its value under the pointer
- Export • Save as SVG, PNG, CSV or PDF
About JDX
JCAMP-DX was made in 1988 so infrared spectra could travel between spectrometers of every brand, and IUPAC grew it for NMR and mass spectra, while UV, Raman and other spectra are written the same way. Instruments export it, the NIST Chemistry WebBook hands out its IR and mass spectra in it, and spectral libraries share it.
It's text: labeled records like ##TITLE=, ##XUNITS= and ##YFACTOR=, then the points, often packed with ASDF's letters, which write each value's first digit, the differences between values and their repeats as single characters. A file can hold many spectra, linked as blocks, and a mass spectrum is a table of peaks.
Filepeek reads it in your browser, unpacks the points and draws the spectrum on paper with the axes chemists read: wavenumbers and ppm running right to left, transmittance's bands hanging down and a mass spectrum's lines. It labels the peaks, reads the curve under the pointer, sums up its records in Tree, and Export saves the spectrum as SVG, PNG or PDF, or its points as CSV.
JCAMP-DX spectrum
.jdx • .dx • .jcamp
Format
- MIME type
- chemical/x-jcamp-dx
- Made by
- JCAMP, the Joint Committee on Atomic and Molecular Physical Data, now looked after by IUPAC
- Released
- 1988
Inside the file
- Records
- ##LABEL=value
- Points
- Packed as ASDF
- Spectra
- IR, Raman, UV, NMR, MS
- Written as
- Text
Opens in every browser
Filepeek opens JCAMP-DX files in Chrome, Edge, Firefox and Safari, on phones too. On their own, browsers download them or show them as text.
- YouChromeOpens through Filepeek
- YouEdgeOpens through Filepeek
- YouFirefoxOpens through Filepeek
- YouSafariOpens through Filepeek
Apps that open JDX
- WindowsJSpecView, free • SpectraGryph and MestReNova
- MacJSpecView, free • MestReNova
- iPhone and iPadNo app opens it
- AndroidNo app opens it
Questions
How do I open a JDX file?
Drop it on this page or choose Peek a JDX. The spectrum opens drawn in your browser, its peaks labeled, with nothing to install.
Why does my IR spectrum run backwards?
Infrared spectra are read from high wavenumbers on the left to low on the right, and NMR from high ppm to low, as chemists always draw them. Filepeek draws them that way.
Can I get the numbers out?
Yes. Choose Export, then Save the points as CSV, which Excel, Origin and Python read, the packed values unpacked.
My file holds several spectra. Where are the others?
The picker at the top steps through them, each by its title, like an IR and a mass spectrum linked in one file.
Why does my .dx open as text?
A .dx opens as a spectrum when it starts with ##TITLE=, as JCAMP-DX does. Other programs name other files .dx too, and those open as their text.