Preview Panel

Know before you open. The preview panel renders images, video, audio, code, PDFs, fonts, hex dumps, and more — all inline, no external apps required.

Table of contents

  1. What is it?
  2. Toggling the panel
  3. Supported file types
    1. Images
    2. Video
    3. Audio
    4. Text and code
    5. PDF
    6. Markdown
    7. CSV and TSV
    8. Fonts
    9. Binary and unknown
    10. Folders
    11. Shortcuts (.lnk files)
  4. How it works
  5. Metadata shown
  6. Settings
  7. Tips & gotchas
  8. See also

What is it?

The preview panel is a side panel that automatically shows a rich preview of whichever file you have selected. It supports 10+ file categories covering almost everything you’ll actually care about previewing — from JPEG photos to PDF first pages to font glyph samples.

For a larger, modal-style preview that takes over the window, see Quick Look.

Toggling the panel

Shortcut Action
Ctrl + P Toggle the preview panel
Ctrl + Shift + P Toggle the preview panel (alternate binding)

The preview panel is per-pane — if you are using Split View, each pane has its own preview panel that you can show or hide independently.

Supported file types

Images

JPEG, PNG, GIF, BMP, WebP, TIFF, and more. The panel shows the image along with metadata: resolution, file size, last modified date, and creation date.

Video

MP4, MKV, AVI, MOV, WMV, WEBM, and more. Playback metadata (duration, codec, resolution) is displayed alongside a thumbnail.

Cloud-only MP4 files are supported too — Span Finder uses the Shell thumbnail cache to render them without triggering a download.

Audio

MP3, AAC, M4A, and more. The preview shows artist, album, track title, and duration pulled from the file’s tags.

Text and code

30+ text extensions are recognized: .txt, .json, .xml, .csv, .md, and most source-code extensions. Previews render with syntax-aware display.

PDF

First-page preview for any PDF.

Markdown

.md files render with proper Markdown formatting — headings, lists, code blocks, links. The preview respects your current light/dark theme.

CSV and TSV

Comma-separated and tab-separated files render as an interactive table (up to 200 rows).

Fonts

Font files (.ttf, .otf, .woff, etc.) show a glyph sample with metadata.

Binary and unknown

For unrecognized or binary formats, Span Finder falls back to a hex dump viewer that shows the first 512 bytes of the file in hex plus ASCII. You can turn the hex viewer off in Settings if you never want it.

Folders

Selecting a folder shows its size, item count, and creation date. Folder sizes are computed in the background with caching so that repeat hits are instant.

Shortcuts (.lnk files)

Windows shortcut files (.lnk) are handled intelligently:

  • If the shortcut points to a folder — the target folder’s contents appear in the next Miller Column, as if you had navigated there directly.
  • If the shortcut points to a file — the preview panel shows the target file’s content (image, text, PDF, etc.) rather than the .lnk file itself.
  • If the target no longer exists — the .lnk is treated as a generic file.

How it works

  • 200 ms debounce — Rapidly changing your selection (e.g. arrow-key scrolling through a long list) waits 200 ms before actually rendering, so Span Finder never wastes work previewing files you immediately scroll past.
  • Cloud-safe — For cloud-only files (OneDrive, iCloud, Dropbox), the panel uses the Shell thumbnail cache and never triggers a download.
  • Remote files — Previews work on files served over FTP, FTPS, and SFTP connections too.
  • Thumbnail limit — Files larger than 20 MB skip local thumbnail decoding and fall back to Shell Thumbnail API caching.

Metadata shown

For most file types the preview panel displays:

  • File name
  • Full path
  • Size (human-readable)
  • Last modified date
  • Creation date
  • Type (e.g. “JPEG image”, “MP4 video”)
  • Format-specific metadata (resolution for images, duration for audio/video, etc.)

Settings

Preview-related settings live under Tools & Integration in Settings (Ctrl + ,):

  • Show thumbnails — Master on/off for thumbnails and previews
  • Show hex preview — Toggle the binary hex-dump fallback
  • Quick Look on Space — Enable Space for the modal Quick Look

Tips & gotchas

Tip: Hide the preview panel with Ctrl + P when you are doing repetitive file operations — you get more room for file lists and Span Finder skips the preview rendering work entirely.

Tip: For a bigger preview or to browse through files with arrow keys while previewing, use Quick Look instead.

Tip: Cloud-only videos (files not yet downloaded from OneDrive/iCloud/Dropbox) still show a thumbnail. Span Finder uses the already-cached Shell thumbnail — it never forces a cloud download.

Gotcha: Very large files (>20 MB) skip the direct-decode thumbnail path and rely on the Shell thumbnail cache. If Windows hasn’t cached a thumbnail yet, you may see a generic icon until it does.

Gotcha: Some PDF producers create files with missing first-page resources. Span Finder falls back to a generic PDF icon when that happens.

See also