C172 pilot reported an engine power loss during climbout. Diverted and landed uneventfully.

Narrative

On Day 0 around XA:30am at ZZZZ; started performing a complete preflight on a Cessna 172S. After a successful preflight everything checked out perfect. Proceeded to start the engine; apart from all standard communication procedures with ATC I performed an engine run up which checked out perfectly. After departure from ZZZZ Runway XX; climbed to 500 ft MSL on the low offshore transition to the east; about 8 nm north east from ZZZZ1 the engine became really rough and started to slowly loose power. I got to climb to at least 1300ft MSL; contact ZZZZ1 tower and requested [priority] landing at Runway XX if possible as engine kept loosing power and became rougher. As landing was approved at Runway XX it was executed in about 4 minutes after a successful touch down continued to taxi to apron; aircraft was shut down. Post flight was performed; fuel; oil; fluids; and entire aircraft structure and controls checked out perfect; there where no visible signs for the cause of the engine problems (checked by certified A&P) aircraft was secured and locked. Mechanic will work to find the cause for engine problem; everyone returned home safely.