View NDPI files in your browser
The whole slide Hamamatsu's NanoZoomer scanners save. Open one right here and zoom from the glass to its cells. Nothing leaves your device.
Or drop it anywhere on this page
What you'll see
Your slide opens whole, then sharpens tile by tile as you zoom in to its cells, read from the smaller copies the scanner keeps.
- The whole slide • Zoom from the glass to its cells
- Label and the glass • Images of their own
- Measure • Lengths in µm, with a scale bar
- Export • Save the view as PNG or the slide as OME-TIFF
About NDPI
Hamamatsu's NanoZoomer slide scanners save their scans as NDPI, in pathology departments, research labs and teaching collections around the world.
An NDPI looks like a TIFF, with Hamamatsu's own tags and offsets past 4 GB, and keeps the slide as one huge JPEG at each level, cut into pieces by restart markers so a viewer can read a part of it, a picture of the whole glass beside them, and the magnification and the size of a pixel.
Filepeek reads it in your browser, each piece only when it shows, from the level that fits the zoom. The picture of the glass is an image of its own, Measure gives lengths in µm, and Export saves the view as PNG or the slide as an OME-TIFF as big as your device holds.
NanoZoomer Digital Pathology Image
.ndpi
Format
- MIME type
- application/octet-stream
- Made by
- Hamamatsu Photonics, for its NanoZoomer scanners
Inside the file
- Built on
- TIFF, with offsets past 4 GB
- Pixels
- JPEG with restart markers
- Levels
- Full size and smaller copies
- Also
- A picture of the glass
Opens in every browser
Filepeek opens NDPI in Chrome, Edge, Firefox and Safari. No browser shows it by itself.
- YouChromeOpens through Filepeek
- YouEdgeOpens through Filepeek
- YouFirefoxOpens through Filepeek
- YouSafariOpens through Filepeek
Apps that open NDPI
- WindowsNDP.view2, free • QuPath, free
- MacQuPath, free
- iPhone and iPadNo app built in opens it
- AndroidNo app built in opens it
Questions
How do I open an NDPI file?
Drop it on this page or press Peek an NDPI. The whole slide shows first, and it sharpens as you zoom in to its cells.
Can I zoom in to the cells?
Yes. Scroll, pinch or use the zoom buttons. Each level of the slide is read in pieces as it comes into sight, down to the scan's own pixels.
Why won't it open as a TIFF?
An NDPI only looks like a TIFF: its offsets and its single JPEG for each level aren't what TIFF readers expect. Slide viewers read Hamamatsu's way, as Filepeek does.
Can I measure on the slide?
Yes. Turn on Measure and drag across a cell or a region. The length shows in µm from the pixel size the file keeps, and the scale bar follows the zoom.
What about NDPIS files?
An NDPIS lists the NDPI files of a fluorescence scan, a channel each. Each NDPI opens here on its own.