Preview KEY files
without uploading them.

First-slide preview and slide count. Nothing is sent to a server.The picture of the first slide that Keynote saves inside every .key file, and the number of slides — on any computer or phone, nothing is sent to a server.

Drop a file or a folder anywhere on this page

or paste with Ctrl V

PDF · Word · PowerPoint · Excel · images · DICOM
PDF · Word · PowerPoint · Excel · CSV · JSON · Markdown · images · DICOM · NIfTI — all 19 formats

How it works

Choose a .key file
Drop it on the page, pick it with the button or paste it with Ctrl V.
See the preview
The first slide appears with the number of slides in the presentation. Zoom, print or show it full screen.
Need every slide?
Ask the sender to export the presentation from Keynote as PowerPoint or PDF — both open here in full.

19 formats

Everything you can open

Each format has its own viewer. Where we show less than the original program, we say so.

Documents

4 formats

PDFPDFPages, zoom, search, print DOCXWordText, tables, charts, SmartArt DOCWord 97–2003Text onlyParagraphs and tables RTFRich TextFormatting, tables, pictures

Presentations

4 formats

PPTXPowerPointSlides, notes, search, slide show ODPImpressLibreOffice and OpenOffice slides PPTPowerPoint 97–2003Text onlySlide text and notes KEYKeynotePreviewFirst slide and slide count

Spreadsheets & data

3 formats

XLSXExcelAll sheets, search in cells CSVCSVUp to a million rows JSONJSONCollapsible tree or text

Medical scans

2 formats

DCMDICOMCT, MRI, X-ray; series and study folders NIINIfTIResearch MRI in three planes

Text

2 formats

MDMarkdownPreview and source TXTPlain textAny encoding, line wrap

Images

1 format

IMGPNG, JPG, WEBP, GIFZoom, fit, actual size

Guides

Short answers to common file questions

All guides

OfficeHow to open a .key file on Windows or AndroidThree ways to view a Keynote presentation without a Mac.4 min read

All guides

Questions

Is my presentation uploaded anywhere?

No. Your browser opens the presentation directly on your device. The site only loads its own scripts, styles and fonts; the contents, name and bytes of your file are never sent to a server.

Why only the first slide?

Keynote stores the slides themselves in a closed format that only Apple’s apps read. Every .key file also carries a picture of its first slide, and that is what OsonKit shows. To see every slide, export the presentation from Keynote: File → Export To → PowerPoint or PDF.

Can I open Pages or Numbers files?

No. OsonKit recognises them and tells you so; export them from Pages or Numbers as Word, Excel or PDF.

How large can the file be?

Up to 50 MB.

Preview KEY fileswithout uploading them.