Hello all,
I am running electric to a back shed. It is about 180' from the panel in the house. The shed will have little load. Lighting is about 600 watts or about 5 amps. Some battery tenders and chargers. This is really about it..

I was thinking #8 THHN with a 50 amp breaker in the main panel.. then a small subpanel in the shed with the lighting and the outlets broken up on 2 - 20amp breakers.

Is this size breaker in the main panel and wire size OK for this length to make up for loss.

Thank you in advance for any input..

The size circuit is fine, and with my recommendation on the wire the breaker can be increased if needed.

If allowed in your area,I would use #2 aluminum for this long run. It will be not too expensive, I'm not sure but it may be close to the cost of the #8 copper.

#2 will be good to start at least a 1/2 HP motor that distance with a normal voltage drop.

Look for 4wire #2 URD cable, it can be direct buried 24" deep. Use 3" PVC conduit if it crosses a driveway or road. If you can afford it, use the duct the entire length. Buried cable needs a bed of cleand sand 6 " above and below the cable. Conduit offers more protection and allows for replacement if the cable does fail.

Keep the neutral and equipment ground separated at the panel, the neutral is the insulated bar.