If you choose to use legacy CM93 v2 data, use it strictly as a . Never rely on them exclusively for close-quarters coastal navigation, entering unfamiliar harbors, or night sailing. For active navigation, always supplement your setup with current official paper charts, up-to-date ENC digital charts, and a vigilant eye on the water.
: Clear color-coded safety contours protect vessels from grounding.
CM93 v2 is a proprietary vector chart format developed by . First introduced in the 1990s, CM93 was designed for use in Electronic Chart Display and Information Systems (ECDIS) and other marine navigation software.
If you possess a legitimate copy of CM93 charts (
The charts are organized by scale levels, ranging from 'Z' (overview) and 'A' (world scale) to 'G' (detailed harbor plans). cm93 v2 charts download
CM93 v2 is a vector chart dataset originally produced by , a leader in electronic cartography. Unlike raster charts (scanned images of paper charts), CM93 v2 offered:
Today, CM93 v2 charts exist in a peculiar limbo. They remain widely used despite being officially discontinued, unsupported, and heavily pirated. For many, they are a "good enough" global basemap; for others, they are a dangerous relic that should never be used for primary navigation.
: Users can adjust the "Detail Level" in software to balance screen complexity with processor speed.
and other regional cruising blogs often maintain links to specific geographic sets (e.g., SE Asia, Western Pacific). Nautical Communities: If you choose to use legacy CM93 v2
Downloading the files is only the first step. Installing them properly is crucial.
Click "Add Directory" and select the top-level directory of your extracted CM93 folder (the one containing the individual region folders like 00300000 ).
Technically, the CM93 v2 dataset is a collection of folders and files with a specific structure. In the top directory, you'll typically find an empty file with the " .EXD " extension (e.g., 20110803.EXD ), where the number indicates the edition date in YYYYMMDD format. The core of the dataset is a series of numbered subfolders (like 00300000 , 01500060 , etc.), which contain the actual chart data files. These folders correspond to specific geographic grid cells, a topic we'll explore in more detail below.
: The last major updates to the CM93 v2 database were roughly around 2011 . While useful for general planning, they should not be used as your primary source for navigation in hazardous areas . : Clear color-coded safety contours protect vessels from
: Once downloaded, these charts are fully functional without an internet connection. Crucial Drawbacks & Risks Installing Charts - OpenCPN
If you use a modern smartphone, tablet, or dedicated chartplotter, utilizing official apps like or the C-MAP app provides fully updated, legally compliant vector charts with features like autorouting, live weather overlays, and community edits for a reasonable annual subscription. Summary: A Tool for Planning, Not Navigating
The CM93 v2 chart format is a piece of marine navigation history. Its legacy as a pioneering vector chart format and its widespread use have cemented its place in the community. However, the charts in circulation today are almost entirely unauthorized copies containing data that is at least a decade old.