What Is a GRD File?

This article explains which file formats use the GRD file extension, plus how to open or convert your file.

What Is a GRD File?

A file with the GRD file extension might be an Adobe Photoshop gradient file. These files are used to store presets which define how multiple colors should blend together. Use one to apply the same blending effect to multiple objects or backgrounds.

Some GRD files may instead be Surfer grid files, a format used for storing map data in either a text or binary format. Others might be used as encrypted disk image files in PhysTechSoft's StrongDisk software.

How to Open a GRD File

GRD files can be opened with Adobe Photoshop and Adobe Photoshop Elements. By default, the built-in gradients that come with Photoshop are stored in the program's installation directory under the Presets\Gradients folder. This is usually in a folder like this:

C:\Program Files\Adobe\Adobe Photoshop <version>\

You can open the file manually if double-clicking it doesn't work. Choose the Gradient Tool (keyboard shortcut G) from the Tools bar. Then, at the top of Photoshop below the menus, select the color that's showing so that the Gradient Editor opens. Choose Import or Load to browse for the file.

The free online image editor Photopea is very similar to Photoshop and can also import a GRD file. With the gradient tool selected, use the arrow next to the color option at the top of the screen to see all your gradient options. There's another menu in that window that lets you choose Load .GRD.

Surfer grid files can be opened using Golden Software's Surfer, Grapher, Didger, and Voxler tools. If those programs aren't working, try GDAL or DIVA-GIS.

Your GRD file is most likely in one of the formats already mentioned, but if not, it might be an encrypted disk image file. The only way to open it would be with the StrongDisk Pro software from PhysTechSoft, via its Mount > Browse button.

Other formats may also exist that use this extension. If your GRD file doesn't open with the programs we've already mentioned, try using a free text editor to open the file as a text document. If you can manage to find any readable text in the file, like at the very top or bottom, you might be able to use that information to research the program that was used to create your specific file.

How to Convert a GRD File

GRD files used in Photoshop can be converted to PNG, SVG, GGR (GIMP gradient file), and several other formats with cptutils-online.

The ArcGIS ArcToolbox can convert a grid file to a shapefile with the SHP file extension. Follow these steps on Esri's website for instructions on how to do this.

You normally need some sort of file converter before you can convert a file to a different format. However, in the case of a Surfer grid file, you should be able to just rename the GRD file to an ASC file and then open it directly in ArcMap.

Encrypted disk images can't be saved in any other format.

Still Can't Open the File?

If your file doesn't open with the suggested programs above, you might be confusing a completely different file format for this one. This can happen rather easily if the extensions are similar.

For example, a file ending in GDR might at first glance look like it has something to do with GRD files. But in reality, they're font files used by Symbian OS devices.

RGD files are similar, but are used for saved games in Raft. Another similar one includes REG used by the Windows Registry, as well as RDCman config files that end with RDG.

You can see now just how easy it can be to misread the file extension and try opening a completely unrelated file in one of the GRD openers above. If you're in this situation, research the actual file extension to learn more about the format and what program you need in order to view/edit/convert it.