Hyperlinks

Hyperlinks in documents

SumatraPDF supports two different kinds of “links” in PDF and other documents. They behave differently and are controlled differently.

Embedded hyperlinks #

These are part of the PDF file — created by the author in Word, LaTeX, Acrobat, etc. They appear in every standards-compliant viewer. SumatraPDF follows them on click:

jump to another page or destination in the same file
open another file
open a URL in the default browser (http://, https://, mailto:, …)

In restricted mode, launching external URLs can be limited with LinkProtocols in sumatrapdfrestrict.ini (default: http,https,mailto).

Auto-detected links (plain text) #

SumatraPDF also turns plain text that looks like a URL or email address into a clickable link, even when the PDF contains no hyperlink annotation. For example, exporting www.example.com as plain text from a word processor creates a clickable link in SumatraPDF but not necessarily in every other viewer.

This follows a long-standing PDF viewer convention (Adobe Reader does something similar). Users who treat unexpected links as a security concern often ask about disabling it — see discussion #5703.

Disable auto-detected links only #

In advanced settings:

DisableAutoLinks = true

Save the settings file. Embedded hyperlinks that exist in the PDF file itself are not removed — only automatic detection of URL-like text is disabled.

Restricted mode: block following links #

sumatrapdfrestrict.ini can disable opening URLs from documents entirely:

[Policies]
DiskAccess = 0

or narrow allowed protocols:

LinkProtocols =

An empty LinkProtocols value blocks all protocol handlers. This is stricter than DisableAutoLinks — it affects embedded links too, not just auto-detection.

See Configure for restricted use and the full restrict.ini reference.

Navigating after following a link #

Internal links (footnotes, table of contents, cross-references) move you within the document. To return:

Alt + Left or Backspace — go back in navigation history
Alt + Right or Shift + Backspace — go forward

See Scrolling and zooming.

CHM and EPUB #

CHM files use HTML links; some ms-its: links open topics inside the help file.
EPUB links are HTML anchors; external URLs open in the browser.