OkMap Tutorial - Creating a Garmin Custom Map

Published on April 15, 2026 - 3 minute read

OkMap tutorial for creating Garmin Custom Maps in KMZ format from georeferenced raster maps.
Garmin Custom Maps allow you to use custom maps and offline maps on Garmin GPS devices while preserving accurate geographic positioning.
In this video, we will show how to convert a georeferenced raster map into a Garmin-compatible KMZ file and verify the final result in Google Earth.
OkMap allows you to create KMZ maps optimized for Garmin GPS devices, transforming georeferenced raster maps into maps that can be used even without an Internet connection.

Procedure:

• Load the map to be converted into a Garmin Custom Map
• Adjust zoom level and area of interest
• Open the Map Management - Map Tiling menu
• Set output to Garmin Custom Map (KMZ)
• Check format (JPG) and quality
• Verify the number of generated tiles
• Remove unwanted tiles (CTRL + left click)
• Save as KMZ file
• Check the map in Google Earth

Tips:

• Check Garmin device limits (maximum number of tiles and file size)
• Remove legend tiles or unnecessary tiles
• Keep JPG quality between 80% and 90%
• Reduce resizing factor if too many tiles are generated
• Verify the final result in Google Earth before transferring the KMZ file to your Garmin device

Common errors:

• Using too low JPG quality (< 75%)
• Exceeding device tile limits
• Creating tiles that are too large (e.g. > 1024 px)