Also, the wing shape and nose shape. The 777 tapers in far more than the 757 around the cockpit. The 757 has a slightly different wing sweep and flap design. The 777 also doesn’t have winglets, and the 757 almost always does.
But yeah, for me the gear gave it away, it’s where I always start when IDing aircraft (assuming it’s extended, and not something super obvious like a 747).
Also, the wing shape and nose shape. The 777 tapers in far more than the 757 around the cockpit. The 757 has a slightly different wing sweep and flap design. The 777 also doesn’t have winglets, and the 757 almost always does.
But yeah, for me the gear gave it away, it’s where I always start when IDing aircraft (assuming it’s extended, and not something super obvious like a 747).