Combat level

A player's, monster's, or NPC's combat level indicates the difficulty in defeating them in combat. In the very early days of RuneScape classic, players started out as Level 1 Combat, and then as Level 3 later; but this was changed and now all new players start out at Level 4, with the maximum level for RuneScape being level 200, while in RuneScape Classic it is Level 123, and in DeviousMUD the highest an account ever reached was 52. Combat level is calculated by taking into account the following skills:
 * Attack or Strength or Ranged or Magic
 * Defence

The formula for working out one's combat level is: X + Defence + 2, where X is the highest out of Attack, Strength, Magic or Ranged.

This will give a maximum combat level of 200, for any player with 99 Defence and a single 99 in any "damage" stat. The minimum combat level will be 4 (1+1+2).

Constitution, Summoning and Prayer does not affect combat level.

As stated by Mod Rathe, the new formula is designed to streamline the calculation of combat level.

The combat level system is supposed to apply to monsters as well. In the beta, most low level monsters have an increase in combat level. For example, the weakest goblins are level 4 instead of 2, and guards are level 50 instead of being in the 20s. Many high level monsters have their combat levels decreased to being deceptively low. TzTok-Jad, for instance, becomes a level 140 while still being a challenge to higher levelled players.

The new system also does not explain how Forgotten mages could be level 198 while they wear celestial robes that requires 99 Magic and Defence, which should give a combat level of 200.

Trivia

 * Before the combat update the minimum combat level was 3 and the maximum was 138 for members and 126 for free-to-play.
 * According to the formula, it is possible to obtain 99 Summoning, Prayer, and Constitution while staying at level 4. Under the old Combat level calculations, a player with these stats would be level 50.