Honestly reaching max level in Borderlands 4 is when the real game actually starts you know, Mayhem 10/11 farming and raid bosses and optimized endgame builds and all that good stuff, the story campaign gets you to roughly level 35-40 but the final grind to level 72 can be painfully slow if you don't know the right spots and tbh I learned this the hard way on my first character spending like 30 hours grinding the wrong content like an idiot, so here's the fastest XP methods in BL4 based on actually playing through them multiple times and figuring out what works and what's a waste of time, basically do these and you'll hit max level in no time

Method 1: Scraptrap Nest (Fastest Overall)

So the Scraptrap Nest is hands down the fastest XP farm in the entire game and I mean by a lot, location is the Compactor in Trashlantis wich requires the Handsome Jackpot DLC, the XP rate is like 10-15 levels per hour at low Mayhem wich is absolutely insane, basically the nest spawns waves of scraptraps that are these small low-health enemies that give excellent XP per kill and the best part is the loop, you kill the Scraptrap Prime at the end then exit the container and re-enter without save-quitting and the Prime respawns and the wave cycle repeats infinitely, no save-quit required its non-stop combat and tbh it's mind-numbingly boring after a while but the XP gain is so good you kinda have to do it, use a splash-damage weapon like the Flipper SMG or Complex Root sniper to clear waves in seconds and you'll blow through levels 13 to 65 before you even realize it, anyway this method is best for levels 13-65 and I've used it on every single character I've leveled

Method 2: Slaughter Shaft (Best Without DLC)

And if you don't have the DLC the Slaughter Shaft is your best bet, location is Konrad's Hold on Pandora in the base game and XP rate is about 8-12 levels per hour wich is still really good honestly, the Slaughter Shaft is a Circle of Slaughter arena with 5 rounds each with 4-5 waves, enemies are exclusively COV who have generous XP values and the whole thing flows really nicely once you get into a rhythm, complete all 5 rounds on the highest Mayhem level you can handle and between rounds the XP counter shows massive gains wich is super satisfying, use corrosive and fire weapons because COV enemies have armor and flesh respectively, and the final boss of round 5 named Titan drops legendary class mods as a bonus wich is a nice cherry on top

Method 3: Graveward Boss Farming

Graveward is the most farmed boss in BL4 for good reason honestly, location is The Floating Tomb on Eden-6 and XP rate is about 6-10 levels per hour, the reason everyone farms this guy is the massive hitbox so literally every shot is a crit with the right weapon plus he has a predictable attack pattern and generous XP, with an optimized build kills take 10-30 seconds wich is pretty much instant, farm on the highest Mayhem level you can consistently one-cycle him on and just save-quit reload repeat forever, the Queen's Call or King's Call pistol is ideal for this because critical hits return bullets to the magazine and you can just hold the trigger until he dies, I've killed Graveward probably 2000 times across all my characters and I'm not even exaggerating tbh

XP Boosting Stacking

So here's something a lot of people miss, equip Moxxi's Endowment artifact wich increases XP from all sources by 7-15% and any class mod or shield with +XP anointment, the Borderlands Science machine in Tannis's lab on Sanctuary III offers a 25% XP boost for 2 hours for 500 points and you can stack these together, 15% from artifact plus 25% from Borderlands Science is a 40% bonus XP wich reduces the time to max level by roughly 28%, I didn't figure this stacking out until my third character and tbh I felt so dumb for not doing it sooner or whatever

Leveling Roadmap Summary

Level RangeMethodEstimated Time
1-35Story campaign15-20 hours
35-65Scraptrap Nest2-3 hours
65-72Graveward or Slaughter Shaft1-2 hours

Total time to max level is approximately 20-25 hours with optimized XP farming and without optimization you're looking at 35-45 hours, the Scraptrap Nest method literally cuts the grind in half and I can't recommend it enough honestly, and stuff like the Borderlands Science boost and Moxxi's Endowment make a huge difference too, you get the idea