What To Look For
There have been a number of changes to swimming goggles in recent years, producing more comfortable and more durable goggles. Look for rubber gaskets rather than the older foam eye-cups. The gasket is the rim that sits directly against your eyes. Pick a double strap rather than a single. You want something that spreads the tension over the back of your head. The fit is the most important element. If a goggle stays on your face without need of the strap, then you've found a pair with a good fit.
The most common problem people have with swim goggles is with the fit. Rubber gaskets tend to fit best, although Swedish-style goggles, which have no gaskets, can also provide an exceptional fit. Even if a foam gasket pair fits you well, there are still good reasons to avoid them. Foam gaskets tend to separate from the goggles over time, making them more prone to leaks. The foam will eventually compress, changing how the goggles stick to your face. Don't pick tinting arbitrarily. Dark tinting may make goggles more suitable for outdoor use, but it will diminish your goggles' indoor effectiveness.
Where To Buy
Try and purchase swim goggles in a specialty shop that will allow you to try on various models. Nothing is more important than having a pair of goggles that fit your face. Swimming pools will often sell swim goggles, which might be valuable in a pinch.
Most swim goggles can be found between $10 and $20. Even goggles with higher quality parts and special features rarely exceed $30. But the price can increase greatly, upwards of $70, if you get prescription goggles.
It's acceptable to purchase goggles online but only after you have tried the goggles on in person. Know the specifics of your preferred model in advance, so you don't purchase a variation with foam parts or a poor strap.
Carrying an extra strap is absolutely essential, particularly for competition. Breaking a strap without having a spare can quickly end your swimming session. Another useful accessory to have is an anti-fog solution, which can be purchased in portable spray bottles.