What does IP65 mean for LED strips?

Dust-tight and protected against low-pressure water jets - not the same as swimming-pool immersion.

IP67 adds temporary immersion (~1 m, time-limited). Check the manufacturer test.

Is the rating for the strip or the connectors?

Both matter. A rated sleeve with open copper joints will still fail outdoors.

Tools / IP Rating Chart for Lights

IP Rating Chart for Lights

IP rating chart for LED lights and strips: IP20 to IP68 explained - dust, rain, jets, and immersion - so outdoor installs do not fail in month two.

Jump to code Dust need Water need

Code	Solids	Water	Typical lighting use

IP ratings without the catalog haze

Two digits. First = dust/solids. Second = water. Silicone sleeve strip marketed as "waterproof" is often closer to splash-resistant until connectors are sealed.

Indoors dry: IP20 is common
Covered outdoor / wet wall: IP65 is a frequent target
Immersion: IP67/68 and a datasheet depth - not vibes

IP Rating Chart for Lights

IP ratings without the catalog haze

Control the lights after you wire them