what tools do you guys ALWAYS have to have before leaving the house?

is there a common one that almost everybody has?

15mm wrench.

Edit: Also, the 'flat kit', which consists of a 16g threaded cartridge, a chuck, a spare tube, and a set of tire levers.

multitool, tire levers, crecent wrench, chain tool, spoke wrench, pump, and one of these:

Jethro Tule 15mm wrench, a 17-in-1 Crank Bros Multitool and a pair of tire levers. The Jethro Tule is my keyring and stays in my pocket, the other two go under my seat with a spare tube and a patch kit. If I carry my bag I'll have a small pump too, otherwise I'll count on gas stations as I do all my biking in the city.

JChou, stop starting threads and use the search function and the many resources available online. Your questions have been answered many times before.

I always carry: a crescent wrench, mini-pump, at least 6 patches (4 small, 2 large), 1"x1" sandpaper square, self-vulcanizing compound, spoke wrench, whatever size allen that works on chainring bolts, about 25 extra chainlinks and a chain-breaker.

If I ride one of my schwinns, I trade the crescent for a 9/16-5/8 wrench.

oh, and a swiss army knife and 3 tire levers.

yes JChou does start threads, and while they may seem repetitive they are at least relevant. So, it is a bit refreshing to see these questions instead of the first page being full of random OT garbage.

We all start somewhere - whether we choose to state this or not.

JChou, have you tried to meet up with some people from the Bay Area? If not, check out sffixed.com for more local ride info, gatherings, etc.

15mm wrench tire levers chain break spare bits of chain patch kit cresent wrench and a pump or tire flater

Hmm, without fail:

Multi Tool
Wrench
Chain breaker
Spare chain link
Patch Kit
Tire levers
Pump
Light

I just keep all that crap in a Crown Royal bag and throw it in the my bag and, voila! Ret' to go'

keep mine in the cut off leggs of pants turned shants - makes a nice tool roll

Currently in my tool pouch:
multi tool
tire levers
patch kit
schrader adapter
15mm wrench
spoke wrench
lockring tool
cigarette lighter
spare u-lock key

ooo good idea, ill have to remember this when i turn my yearly dickies into shants this spring

https://www.bikeforums.net/members/dutret-31510.html

I always carry:
a small multi-tool w/chain breaker
few extra chain links (whatever was cut off the new chain)
spare tube, patch kit, tire levers
pump or CO2 inflater
15mm stubby gear wrench
a

In the bag:

15 mm box wrench
Patch kit
Tire levers
CO2 inflater
Spoke wrench
Mini crescent wrench
Allen keys
Chain tool
Tube (not all the time, but it is nice)

I have three toolkits depending upon the situation. Just riding around the neighborhood or a quick ride across the bridge (sans mess bag) I carry a 16 gram c02, microflate c02 nozzle, two tire levers, patch kit, and 15mm wrench. it fits in my pocket and the idea is that if something big happens, i'll just jump on the subway. 2nd kit is a bit bigger but fits in a small jandd saddle baq which i usually throw in my bag unless i'm bagless. It has 16 gram c02, second wind mini pump/c02 pump (nice to have a backup hand pump if i run out of c02), tube, tire levers, front and rear knog frog lights, serfas multi tool, and a 15 mm wrench. my last one is just the second one but with a second tube, a couple more c02 cartridges, and a larger topeak mini pump, plus a rediculously large map of all 5 burroughs. that one's for long rides with fix it or carry it home implcations.

Genius!!! I'm putting an extra key in my kit right now.

I wish I would have done this two weeks ago when I lost my keys.

Yeah, I keep a key in my bag, too. Just because.

15mm wrench, hex wrench type multitool, tube, CO2 inflater, tire lever

tube, bike tool, pump, energy bar

I'm feeling woefully unprepared compared to you guys. I sometimes remember to carry a hex multi-tool, mini-pump, lever and patch kit. Sometimes.

all the standard stuff plus sunglasses. commuting would be hell without.

also my cell phone might seem obivious, but it has my boss' number and also the number of a cab company if that sorta rescue is needed.

all my schit is always in my bag so i know where it is...
crescent wrench.
box wrench for my rear wheel.
set of cone wrenches (i need the 17mm to remove my front wheel, it's gummed up so i gotta hold the spacers in place when i loosen the track nuts).
ascent mini-tool.
chain breaker.
tire levers / pump / tubes / patches.

and i've been carrying spare keys in my kit for a while: spare u-lock keys, cable keys, house key, occasionally my car keys find their way in there.

plus... my bag always has a blinkie on it, and i keep my front light in my bag for when i'm riding in the boonies and it matters.

Multi-tool with tire levers and chain tool, patch kit, spare chain link, spare tube, 15mm wrench (all in my wedge bag)
framepump (on the frame)
cell phone - tool of last resort (jersey pocket)
Energy bar(s) for long rides (Jersey pocket).