Extract text from Harvard Graphics charts (CH3)
To convert CH3 charts to another format, you need Harvard Graphics or other Vector Image software.
To convert other file formats to the "Legacy Presentation Chart" file type, you need software like Harvard Graphics or a similar tool.
The .CH3 file extension is exclusively used for Harvard Graphics 3.0 Chart files. Originally developed in the late 1980s by Software Publishing Corporation (SPC), Harvard Graphics was the dominant business presentation software for MS-DOS before Windows-based tools took over the market. A .CH3 file stores binary vector graphic data, text, axis information, and chart formatting used to print slides or display on-screen presentations.
The primary disadvantage of the .CH3 format is severe obsolescence. It is a closed, proprietary binary format that has been abandoned for decades. Modern operating systems and web browsers cannot natively read it. While early versions of Microsoft PowerPoint included legacy import filters for Harvard Graphics, these were removed years ago for security and codebase modernization. Users with archived .CH3 files face significant accessibility roadblocks, as their historical business data is trapped in an unsupported ecosystem.
Converting .CH3 to modern, standardized formats like PDF (for document preservation) or SVG and PNG (for graphics) is the best solution. However, standard online converters routinely fail to process it. Because it is an undocumented format, reconstructing the specific DOS-era fonts and vector rendering logic without the original software is practically impossible for generic tools.
This format is notoriously difficult to open or convert. Often, the only reliable way to properly read or export the visual data is to run the original MS-DOS application inside an emulator. Our platform will inspect the binary structure and extract readable ASCII text, such as presentation notes or chart labels. If our analysis detects a supported underlying or embedded format, partial viewing or conversion may still be possible.
Convert.Guru analyzes your CH3 file, detects the exact format, and lets you read the text inside.
Users also converted PRS, PR4, EX3, CH4 and CHO files.
If you want to convert CH3 file to CHO, you can use Harvard Graphics or similar software from the "Presentation Chart Storage" category. In the File menu, look for Save As… or Export….
To convert files to CH3, try Harvard Graphics or another comparable tool in the "Presentation Chart Storage" category.
The history of Convert.Guru began over 25 years ago in California with Tom Simondi’s file-format database. A former contributor to Space Shuttle development and a software pioneer of the 1980s, Simondi established a trusted resource for file type analysis that was even referenced by Microsoft Windows XP. Today, we use modern technology to process and convert thousands of file formats while continually improving our CH3 converter.