On the Technological Achievement Tiers, the Forerunners are a Tier 1 civilization, a.k.a. "World Builders."
- "The species has the ability to manipulate gravitational forces, create AI with full sentience, fabricate super-dense materials, perform super-accurate Slipspace navigation, the ability to create life, and the ability to create worlds."
On the same scale, the Covenant are a Tier 2 civilization, a.k.a. "Interstellar."
- "The species has the ability to perform exceedingly accurate Slipspace navigation, near-instantaneous communication and man-portable application of energy manipulation."
Thus, the Covenant are not more advanced than the Forerunners. (Text in quotations taken from the Halo Nation article, Technological Achievement Tiers.)