In my case, for fixed blade, "EDC" means "urban carry" (I carry larger fixed blades for outdoor/bush use). The largest fixed I carry for EDC is a 4" blade. Beyond that they become cumbersome and too obvious for urban environments.
I carry folders mostly but when I do EDC a fixed blade it is usually one of four out of a collection of many. My favorite one is crazy I know, but...
Tekna Ocean Edge dive knife I've had since the '70's. Probably 420 steel. Mine takes screamin' edges and has never rusted or tarnished a spot! Seki, JA made. 3.5" blade. I leather wrapped the handle some time ago. It's my favorite fixed blade EDC because i like the blade design--part serrated (great serration pattern I might add) stiletto/dagger style. IMO, it's the coolest, most unique knife/sheath combination ever made. The versatility is amazing as the spring-locked sheath design allows it to be carried securely in any manner from boot to belt to necker, horizontal, vertical, upside down, etc., yet quickly drawn. It has always been the primary fixed blade carry package for me in town, on the water, in the water, motorcycling, backpacking, climbing, traveling....anyplace. The whole package is the perfect size. It's been more places with me than any fixed blade I own.
Original DPx HEST fixed blade by Rowen. Appx. 3.5" blade in 1095 with good ol' Rowen heat treat. The best throw-it-in-the-bag-and-go knife I know of. Good Kydex sheath. Tough, do anything knife. Best "knockaround" knife out there, IMO.
Gryphon M-10 which I acquired a year or so ago based on a recommendation I saw here. Great, Terzuola-designed 4" VG-10 drop-point bayonet style blade with perfect balance and feel. An excellent Boltaron sheath with a Tek-Lok for multiple carry positions. Most comfortable belt-carry I've ever had for a 4" blade. Good boot-carry too. Importantly, it has the most comfortable, secure-in-hand handle of any knife I own.
Buck CSAR-T Liason. Appx. 3.25" blade, 400-series steel that takes a great edge (Buck heat treat?). Tanto style blade. Most minimal Kydex sheath I've ever seen; holds the knife securely too. Makes a fantastic stealthy horizontal carry rig with the addition of two zip-ties through the sheath grommets; whole thing's the width of an average belt. Great for traveling seated in a car. Very quick cross-draw access anywhere.
Now that I'm on this I also have to 'honorable mention' my Becker BK-11 san mai. "Becker Necker." Tough and versatile knife for anywhere.