The Kardashev scale is a method of measuring a civilization's level of technological advancement, based on the amount of energy a civilization is able to use for communication. The scale is hypothetical and regards energy consumption on a cosmic scale. It was proposed in 1964 by the Soviet astronomer Nikolai Kardashev.
Credit can be given to the Kardashev Scale Wiki
Here is the scale
- Tier 0: This is harnessing and using the power of resources from a home planet
- Tier 1: This is when a civilization uses the power of a planet to its full potential
- Tier 2: This is using the power of stars, this has a wide range from just the Sun to a chunk of the galaxy
- Tier 3: This is harnessing the power of the entire galaxy, this is when super-races start appearing
- Tier 4: These civilizations can illuminate galactic superclusters with their tech
- Tier 5: These civilizations are universal, there tech is physics-breaking even to the standards of Tier 3/4 Civilizations
- Tier 6: This is when stuff gets really crazy, beings here view the universe the same way we would view a single city. These beings are multiverse.
- Tier 7: The ultimate tier, time and space are nothing but toys to them and they control more than just a multiverse.
To see where the civilization you are looking at is, use this formula
So for example, Civilization X can output 3.6e27 watts with their technology. Plugging that in here, that civilization is at the beginning of tier II.
More can be found from these sources