Hi Product Hunt 👋 What inspired it I didn't start out building a file viewer. I started researching tools for e-learning (SCORM) files, ran the keyword research, and found almost nobody searches for them. While digging through forums, I kept seeing a different question asked again and again: "How do I open this .eml / .msg file without Outlook?" and "How do I get this KML onto my Garmin as a GPX?" The problem The usual answers were "install this desktop program" or "upload your file to our free online viewer." Uploading a private email (contracts, invoices, personal messages) to a random server just to read it felt wrong. So OpenFileKit does everything inside your browser. Your file is read locally and never uploaded – you can open your browser's network tab and watch nothing leave. No signup, free. What it does today - Open EML, MSG (Outlook) and MBOX files, download attachments, save as PDF - View GPX and KML/KMZ tracks on a map with distance and elevation - Convert KML ↔ GPX How the approach evolved - Plan A was "one tool page per file type." Testing with real-world files changed a lot: old Outlook files store text in local code pages (Russian and Chinese emails came out garbled until we handled that), and some .msg files turned out to be archive shortcuts, not real emails. - Emails are hostile territory. Tracking pixels and scripts are blocked by default, and a malicious email can't fake its own "From" line, because the sender details are drawn outside the email's sandbox. - I dropped two conversion libraries that depended on abandoned packages and wrote the GPX/KML writers by hand instead. - Safari behaved differently from Chrome when handing a file from the home page to a tool, so that got its own fix. What I'd love from you Try a file that's given you trouble, especially an old Outlook .msg, and tell me if it breaks. And tell me which file type you'd want next (embroidery files like DST/PES are on my list).

OpenFileKit

opening EML and MSG files or converting GPX and KML.

opening EML and MSG files or converting GPX and KML.