Like mentioned, just measure the blade.
Now go to Amazon and order just the blade insert, not the entire assembly. That way you're not throwing away all the metal wiper assembly. It's only like $10 with free shipping if you're a Prime member. Most all stores now carry the entire assembly instead of the economical and environmentally sensitive insert. But you can still get just the insert.
Here's a link to a 26" insert to get you started...they can be cut. This one is 6mm but some are wider so measure that too. Mine is 28" but didn't have any trouble finding it on Amazon.
Rubber wiper blade.