How to Find Information About a Specific File Extension on Open My Files

Updated

To look up a file extension on Open My Files (openmyfiles.com), use the search box on the homepage to enter the extension, or browse the "Top File Format Categories" section and open the category that matches the file type. The site describes itself as a "File Information Directory" and organizes entries under categories such as Archive, Audio Files, Data, Raster Image Files, Spreadsheet Files, Executable Files, Vector Image Files, and Video Files.

Search Directly by Extension

This is the fastest route when you already know the extension (for example, .xlsb or .dpx).

  1. Open the openmyfiles.com homepage.
  2. Locate the search field labeled "Search for:".
  3. Type the extension, with or without the leading dot (e.g., xlsb or .xlsb).
  4. Submit the search and open the matching result.

Expected result: a page for that extension. If no entry appears, the site likely has no page for it yet — try the category browse method below to confirm.

Browse by Category

Use this when you don't know the exact extension, or when search returns nothing.

  1. On the homepage, scroll to "Top File Format Categories".
  2. Pick the category that fits the file's likely purpose. The homepage lists, among others:
    • Archive — e.g., DESKTOP, IES, ISO, ZIP
    • Audio Files — e.g., M4P, PCM, COPY, DSF, AU
    • Data — e.g., ODP, XML
    • Raster Image Files — e.g., ITHMB, DPX, MAC, EXR, SCP
    • Spreadsheet Files — e.g., XLR, XLS, XLSB, XLSM, XLSX
    • Executable Files — e.g., XLM, AHK, ACTION, JSF, SCRIPT
    • Vector Image Files — e.g., POSTSCRIPT, DRAWING, IDEA, PUPPET, PFD
    • Video Files — e.g., OGV, VID, H264, QT, 264
  3. Open the category and scan its list for the extension.
  4. Select the entry to read its description.

Expected result: a category listing where each extension links to its own information page.

Choosing Between the Two Methods

Situation Best method Why
You know the extension exactly Search box One step to the entry
You only know what the file does (e.g., "a spreadsheet") Category browse Narrows by file type first
Search returns no result Category browse Confirms whether the format is listed at all
You want to compare related formats Category browse Shows sibling extensions in one list

Common Snags

  • Category names are broad. A file may sit under a category you didn't expect, so check a second category before concluding it's missing.
  • The directory is not exhaustive. The homepage shows only "top" categories and a sample of formats per category; an unlisted extension may simply not have a page.
  • Extensions are case-insensitive in practice. XLSX and xlsx refer to the same format; enter either.

The site does not state pricing or login requirements on the pages reviewed, so treat access details as unconfirmed until you see them on the site itself.