The Geocache Viewer covers three delivery surfaces: the browser extension, the bookmarklet, and the web viewer at /tools/gcviewer/. Cache page contents — the HTML you load via the bookmarklet, extension, paste, or JSON upload — are parsed and rendered locally in your browser and are not uploaded to CacheSleuth or transmitted to any third party.

CacheSleuth services the viewer calls

• Translation (cs-translate.cachesleuth.com). If you pick a non-English language from the footer dropdown, the page sends its static UI strings — labels, headings, FAQ text — to CacheSleuth's translation worker. The cache page contents are never included. Translations are cached in your browser so the same string is not re-sent on later visits.
• Header search autocomplete. The site-wide search box loads a static index file (/search-index.json) from CacheSleuth. Your search query stays in your browser.

Resources loaded by the viewer

• Cache type and attribute icons are served from i.cachesleuth.com, a CacheSleuth-operated image host.
• All JavaScript, CSS, and fonts the viewer needs — coordinate libraries (OS Grid Reference, MGRS), the Plus Code helper, the DOMPurify HTML sanitizer, the Prism syntax highlighter, and the Lucide icon set — are vendored on CacheSleuth and loaded from the same origin. No third-party CDN (jsdelivr, cdnjs, etc.) is contacted to render the viewer.
• Images, avatars, and log photos referenced in the cache page (typically on img.geocaching.com, s3.amazonaws.com, or other hosts the cache owner chose) are fetched directly by your browser when the viewer renders them. The viewer sets a no-referrer policy on outbound requests, but the destination server still sees that your browser requested the image.
• Map and external links (Google Maps, Bing, OpenStreetMap, ArcGIS, geocaching.com, etc.) are plain links — nothing is sent to those providers unless you click through.

Analytics

The viewer itself does not run analytics, ad networks, or tracking pixels. The web viewer is delivered through the rest of the CacheSleuth site, so the cookieless Cloudflare Web Analytics described on the main privacy page applies to visits to /tools/gcviewer/. The browser extension does not run analytics.

What is never sent

Your geocaching.com session, the cache HTML or JSON you loaded, your notes, and anything you paste into the viewer's tools (Text Manipulator, Multi Decoder, My Links, etc.) stay in your browser. The viewer does not upload cache page contents to any CacheSleuth or third-party service.

For questions, please visit the contact page.