An ARH file isn’t tied to one universal purpose, so the best way to identify it is by checking context; many ARH files come from Siemens ProTool—older industrial HMI software—where they act as compressed project packages for storing or backing up HMI work, making this likely if the file came from factory equipment, PLC/HMI technicians, or folders mentioning Siemens, ProTool, WinCC, STEP7, S7, or HMI, while in other cases ARH refers to an ArheoStratigraf project used in archaeology for documenting stratigraphy and building diagrams like a Harris Matrix, which fits if the file came from excavation records or folders labeled contexts, trench, stratigraphy, matrix, or layers.

To identify the ARH type accurately, the quickest diagnostic is opening it with 7-Zip or WinRAR, because some ARH files are essentially archives; if the tool opens it and displays internal folders or files, you can extract them and inspect elements like images, configs, or database items—usually signaling a packaged Siemens/ProTool-style project—while a failure to open means the file might still be valid but proprietary, requiring ProTool or ArheoStratigraf, and you can also try copying and renaming the file to `.zip` or `.rar` in case it’s a simple archive under another name, with the real “correct” method depending on your needs: extraction works if you only want assets, but full project editing needs the original software.

Because many ARH files are formatted as project archive packages, tools like 7-Zip and WinRAR are handy even when you don’t know the program yet; if they open, the internal files—configs, images, logs, databases—instantly reveal the file’s nature and let you extract assets, but if they can’t, the ARH may just be a proprietary project format, and renaming a copy to `.zip` or `.rar` can sometimes expose a normal archive underneath, making this quick test a simple, low-effort way to understand the ARH and extract anything useful.

An ARH file doesn’t correspond to one unified format because “.ARH” isn’t controlled by a global standard and is reused across unrelated software, meaning two files with the same extension may contain totally different structures; context is the key—Siemens automation projects typically use ARH as a compressed HMI package, whereas archaeological setups use it as an ArheoStratigraf project—and proper identification comes from examining its origin, surrounding files, and whether it behaves like an extractable archive.

What this means day-to-day is that “.ARH” is merely a reused extension, so an ARH from automation circles might be a Siemens/ProTool package containing screens, tag sets, alarms, and configs, while an archaeology ARH might instead be an ArheoStratigraf project with stratigraphy and diagram structure, and even matching filenames can hide unrelated data, which is why checking its origin, nearby files, and behavior in 7-Zip is the safest method to determine if it’s an archive or a proprietary project needing the original software.

You can typically pinpoint the type of ARH file by examining the *surrounding clues*—folder names, companion files, and the workflow source—since the extension itself is not definitive; in automation contexts with Siemens, ProTool, WinCC, STEP7/S7, PLC, HMI, tags, or alarms present, the ARH is likely a Siemens ProTool project package, whereas in archaeology folders labeled trench, context, stratigraphy, matrix, layers, or site and bundled with excavation documents or images, it is probably ArheoStratigraf, and if uncertain, attempting to open it with 7-Zip will reveal whether it behaves like an archive or needs its original software.