Some resources for comparing times between short-course (25 yard) and long-course (50 meter) swims are listed at the bottom of this page. However, please read the following first!
USA Swimming does not formally endorse any conversion factors between different courses. Each course (long course meters, short course meters, and short course yards) is unique. For qualification into specific competition, each course has a time standard derived from a specific formula or philosophy.
Pacific Swimming no longer requires that entry times be converted between long course and short course. For meets that require that entry times be proved (such as Junior Olympics, Far Westerns, and certain meets in the senior program), meet entry time standards will be provided in both short course and long course, and you may enter a qualifying time achieved in either course.
However, it is important to note that Pacific Swimming still requires that, when you have achieved a specific class level (for example, B or A) in an event in one course, you are considered to be qualified at that same level in all courses. Accordingly, you must always enter a time which maintains the class for which you've qualified in an event.
For example, if you've achieved an A time in an event short course but have never swum the event or have never achieved at this level in the event long course, you must enter at least a minimum long course A time when you enter the event in a long course meet.
TIME COMPARISON RESOURCES
(NOTICE: DDST is not responsible for the content or actions of any other web site, use of which is at the visitor's sole risk.)
SwimConnection.com will show your current season best times converted to any course. If you are a SwimConnection member you can also display best times from past seasons. Note that SwimConnection does NOT apply altitude adjustments, if any, to your times.
Colorado Swimming course/altitude converter. Also see the formulas used by this converter.
Swimming World Magazine times calculator.