Free online VSI to JPG converter

VSI files are commonly produced by Olympus microscope imaging software, while JPG is accepted by ordinary image viewers, office applications, websites, and photo editors. Converting is useful when a microscope image must be shared without specialized slide-viewing software or reduced to a smaller, broadly compatible file.

What the VSI format is

VSI is the Olympus Virtual Slide Image format used by systems such as Olympus cellSens and OlyVIA. It stores microscope imagery and associated data, often including tiled high-resolution images, multiple scenes, focal planes, channels, and metadata. VSI files are encountered after whole-slide scanning or microscope image acquisition and may be too large or specialized for standard image applications.

What the JPG format is

JPG is a widely supported raster image format using lossy compression. It is suitable for previews, reports, email, websites, presentations, and general-purpose editing because most operating systems and image applications open it without microscopy software.

JPG is usually much smaller than a microscope source file, but it does not preserve VSI-specific metadata, microscope layers, multiple focal planes, or lossless pixel data. Use TIFF or the original VSI when quantitative analysis or maximum image fidelity is required.

How to convert VSI to JPG

Using the online converter

1. Open the VSI conversion page on 101convert.com.
2. Select or drop the .vsi file into the converter.
3. Choose JPG as the output format and start the conversion.
4. Download the resulting JPG file when processing finishes.

This option requires no installed software. Large virtual slides can take longer to upload and process, and the service may export a selected image view rather than every internal VSI series.

Using Fiji and Bio-Formats

1. Install Fiji, which includes the Bio-Formats importer.
2. Open Fiji and choose File → Open, then select the .vsi file.
3. In the Bio-Formats import dialog, select the required series, scene, channel, focal plane, and resolution. Enable autoscaling only if the preview has unsuitable intensity levels.
4. After the image opens, choose File → Save As → Jpeg and set the JPEG quality if Fiji provides that option.

For a whole-slide VSI, export the required downsampled resolution or a cropped region instead of loading the maximum-resolution image. Fiji may open each internal series separately because a VSI can contain more than one image.

Using Olympus software

Open the file in OlyVIA or cellSens, select the required scene or image layer, and use the program's image export command, typically File → Export or File → Save As, with JPG as the output format. Exporting from the manufacturer's software is preferable when channel selection, scale bars, annotations, or microscope-specific metadata need to be controlled before rasterization.

Quality and compatibility limitations

JPG compression can introduce block artifacts and alter fine structures, especially around thin lines, fluorescent details, and high-contrast edges. Choose the highest available JPEG quality and avoid repeatedly opening and resaving the output.

A VSI may contain multiple scenes, channels, z-levels, or resolutions, but one JPG represents only one rendered view. Check the exported image for the correct series, focal plane, orientation, scale bar, and brightness before sharing it. If the source contains transparency, JPG replaces it with a background because JPG does not support an alpha channel.