An sdl file extension is related to the Dive Manager from Suunto. An sdl file contains dive log.
There are 5 other file types using
the SDL file extension!
.sdl - Alias Wavefront Scene Description Language
.sdl - Corel Paradox script
.sdl - SmartDraw library
.sdl - Simple Declarative Language file
.sdl - Web Service Description Language file
What is sdl file? How to open sdl files?
The sdl file extension is associated with the Suunto Dive Manager (SDM), a software for Microsoft Windows operating system, developed by Suunto.
The sdl file stores dive log captured by Dive Manager.
The default software associated to open sdl file:

Suunto Dive Manager 
Company or developer:
Suunto
Suunto Dive Manager (SDM) allows divers to recording, organizing and retrieving dive information from Suunto dive computer. It looks like last version is 5.
Help how to open:
Use Dive Manager to work with *.sdl files.
How to convert:
As far as we know, this .sdl file type can't be converted to any other file format. This is usually the case of system, configuration, temporary, or data files containing data exclusive to only one software and used for its own purposes. Also some proprietary or closed file formats cannot be converted to more common file types in order to protect the intellectual property of the developer, which is for example the case of some DRM-protected multimedia files.
List of software applications associated to the .sdl file extension
Recommended software programs are sorted by OS platform (Windows, macOS, Linux, iOS, Android etc.)
and possible program actions that can be done with the file: like open sdl file, edit sdl file, convert sdl file, view sdl file, play sdl file etc. (if exist software for corresponding action in File-Extensions.org's database).
Hint:
Click on the tab below to simply browse between the application actions, to quickly get a list of recommended software, which is able to perform the specified software action, such as opening, editing or converting sdl files.
Software that open sdl file - Dive Manager dive log
Programs supporting the exension sdl on the main platforms Windows, Mac, Linux or mobile. Click on the link to get more information about Suunto Dive Manager for open sdl file action.
sdl file editor and apps that can edit sdl file - Dive Manager dive log
Programs supporting the exension sdl on the main platforms Windows, Mac, Linux or mobile. Click on the link to get more information about Suunto Dive Manager for edit sdl file action.
Programs that can create sdl file - Dive Manager dive log
Programs supporting the exension sdl on the main platforms Windows, Mac, Linux or mobile. Click on the link to get more information about Suunto Dive Manager for create sdl file action.
Unspecified and all other actions for computer programs working with sdl file - Dive Manager dive log
Click on the software link for more information about Suunto Dive Manager. Suunto Dive Manager uses sdl file type for its internal purposes and/or also by different way than common edit or open file actions (eg. to install/execute/support an application itself, to store application or user data, configure program etc.).
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