USB‑C is the way to go for high‑res external display on MacBook Air M3.

Use USB‑C. HDMI via adapters caps out at 4K 60Hz.

The MacBook Air M3 supports one external display natively through its USB‑C ports (with DisplayPort alt mode). That’ll drive up to 6K at 60Hz — think Apple Studio Display or a 6K monitor like the Dell UP3218K. That’s your maximum.

If you go HDMI via a USB‑C adapter, you’re stuck at 4K 60Hz because basically every USB‑C to HDMI adapter on the market is HDMI 2.0. Even if you find a rare HDMI 2.1 adapter, the M3 Air’s controller doesn’t support HDMI 2.1 output over USB‑C. So don’t bother hunting.

Bottom line: For a big, crisp monitor, plug directly into USB‑C. Leave the HDMI adapter for projectors or old screens.