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GRI Converter
Need to convert GRI files to other formats? reaConverter does it in batch. No file limits, no watermarks, no internet required.
How to Convert .gri Files in Bulk
1. Install reaConverter
2. Select GRI Files
3. Start Conversion
Step by step
See It in Action
For quick and effortless GRI file handling on your PC, reaConverter offers powerful conversion tools with batch processing. Best of all, it works entirely offline — ensuring your sensitive data never leaves your computer.
GIS Toolkit
Do more with your GIS data
Need GRI data as something anyone can open? reaConverter renders imagery and elevation grids into standard images and documents without QGIS or ArcGIS, and works through whole folders in one pass.
- Render imagery, elevation grids and scanned charts to TIFF, PNG, JPG or PDF
- Resize, crop and set DPI on the output in the same run
- Bring tiles, scenes and grids from many sources into one consistent format
- Convert incoming survey and field data automatically with Watch Folders
- Script GIS conversions from the command line for pipelines and scheduled jobs
- Keep cadastral, utility and client data on your PC: nothing is uploaded
User reviews
From those who tried it
Average User Rating:Last updated on July 28, 2026
Questions & Answers
GRI files: Frequently Asked Questions
What are GRI files?
GRI is the binary half of the R raster format, which keeps the cell values separate from their description. The file contains nothing except numbers written one after another, in the type named in the companion .grd header, for example integers of a given size, decimal numbers, or yes-or-no values. The header also gives the number of rows and columns, the byte order, the area covered, the projection, and the names of the layers, so without it the numbers cannot be turned back into a picture. For images with several layers, the values of the layers are stored in the same file, and the layer names are kept in the header. The data are not compressed, so the files can be large. To convert a GRI file to graphics, a program reads the header first, then loads the values according to the declared type, treats empty cells as transparent, and maps the numbers to a grayscale or color scale. One layer gives a single-tone or color-ramped picture, and three layers can form an RGB image. The result can be saved as PNG, JPEG, TIFF, or GeoTIFF with coordinates. Supported by R, ENVI, ArcGIS, and FME, in some cases through an exported header.
Can reaConverter open GRI files?
reaConverter fully supports the GRI file format – open, edit, and export GRI files to any other popular file format with ease.
Do I need QGIS or ArcGIS to convert GRI files?
No. reaConverter reads GRI files on its own, so the conversion needs no GIS installation and no licence. It handles whole folders at once, which suits survey archives, tile sets and data deliveries that have to reach people working in other software.
How do I change GRI to another format?
reaConverter is a user-friendly tool for converting GRI files. Once installed on your computer, it allows you to convert all your .gri files at once with just a few clicks. You can even convert gri images directly from Windows Explorer using the right-click menu — fast and convenient.
Why choose offline conversion with reaConverter?
Keep your sensitive data 100% private with offline processing that never exposes files to cloud risks. Our software meets strict compliance standards (GDPR, HIPAA, CCPA) while handling confidential documents for legal, healthcare and financial sectors.
Can I convert GRI online?
If you only want to convert a few GRI files, you are welcome to try our free online GRI converter.
How can I turn GRI files on my computer to another format?
The best way to convert GRI files on your PC is to get a quality piece of software, such as reaConverter. This software is extremely efficient in managing a wide range of batch files conversions, including conversion from GRI.
How can I automate GRI files conversion?
reaConverter supports all the essential automation features, such as right-click сonversion and Watch Folders, for the most efficient automated file conversion in any software of its kind.
Can I convert GRI files using scripts or the command-line interface?
reaConverter provides full access to all its features from the Windows command-line shell, including the command-line gri converter.
What else can I do with reaConverter?
Convert PDFAdd watermark on imageConvert Gerber imagesChange image color spaceConvert CAD formats
What formats can I convert a GRI file to?
Discover More
Beyond GRI conversion
Convert .gri files in batches of any size, with editing and processing applied along the way. The same tool also handles 800+ other formats, including CAD, medical imaging, and GIS.
