About the LongSwims Database

LongSwimsDB is a repository of structured, cross-linked, verified, quality-controlled data about unassisted long distance open water swimmming (also known as marathon swimming).


The database includes:

The database does not include:

Swimmer Profiles

Profiles are automatically created for swimmers who meet a combined threshold of several factors, including number of swims, the distance of the swims, and how recent they are. There are approximately 4000 profiles out of 22,000 total swimmers in the database.

See included events.

When are new results added?

If the event is already in the database (view list): when they are made available by the organizer/association, AND when we get the chance. Please be patient.

If the event is not in the database, we may not know about it! Please send us a tip.

All results should include at least: date, route description, swimmer names, elapsed times. Also nice to have: swimmer gender, age, nation, hometown.

Standards of Evidence

Annual Organized Races

Official race results published on the event website, or provided directly from the organizer in a common document format such as PDF, CSV, Word, or Excel.

If wetsuits or other swim aids are allowed, unassisted swimmers must be clearly distinguished. Exception: If tow buoys are mandated by the organizer, this does not disqualify the event from inclusion.

No further evidence is required.

Solo Swims Sanctioned by a Recognized Local Association

No further evidence is required.

In some cases, swims pending ratification may be added based on initial reports. These will always be checked with the association's list at the end of the season.

Independent (Self-Organized) Solo Swims

For recent swims (2013 and later): ratification through MSF Documented Swims. Requirements include observer log, GPS data, photos, video, and a narrative summary.

For historical swims (before 2013): at our discretion we may add swims for which the following critical details are available:

Also helpful: logs, photos, newspaper reports, and any other relevant data.

Please contact us with your request.

Note: Unsanctioned swims on routes already covered by a recognized association are not eligible for inclusion in the database.

I want to add a swim to my profile...

Generally we do not have the bandwidth to accommodate such requests. Please consider there are over 22,000 swimmers in the database.

Whenever possible, it is far more efficient for us to import full event results rather than ad-hoc results for an individual swimmer. If you really want to add a result just for you, please join as a MSF member.

Correcting Errors

LongSwimsDB utilizes numerous quality-control techniques in importing data. However, occasionally errors slip through. Please contact us if you notice something.

Known Issues