Seamark keeps your sailing trips as a proper ship's log — legs, crew and charter records, GPX tracks cleaned into honest statistics, and every route drawn on a chart.
No password — we email a single-use link that signs you in. The same link creates your account.
A trip holds its legs, the ship, the ship's company and the charter paperwork. Legs are numbered as sailed — harbour to harbour, with dates, times and notes.
Bring the track from your plotter, watch or phone. Seamark drops the junk fixes — invalid points, duplicate timestamps, speed and acceleration jumps — and keeps an audit of every discard. The same file always yields the same figures.
Distance made good, time under way, average and best sustained speed, night hours from the sun's own timetable. Sustained maxima over a held window — never a GPS spike.
Every voyage learns which countries and seas it visited, derived offline from bundled coastline data. No position ever leaves the server.
Each leg records the wind and the Douglas sea state, typed in as observed — or filled, for wind, with one click from Open-Meteo.
Invite your crew by email; they see the voyages they sailed with you, and nothing else. A public read-only link — off by default, revocable — lets family follow along.
One click downloads the entire log: plain JSON and every track as GPX, cleaned and raw, with the format documented inside. Leave any time and take it all.
A built-in MCP server, behind OAuth: connect Claude or any MCP client, and an agent can do everything you can do in the app.
Seamark is a small, self-hostable app, in English, Czech, German, Spanish and Slovak. Run your own, or start here — and take your whole log with you any time.
Start your log · User manual