How long should my car battery last after a jump start?

I couldn't start my car today, so I got a jump and was able to get home ok. Should I look into replacing my battery, or should it be good for a while longer? I got a new battery about three years ago, and I'd estimate I've driven about 40,000 miles since then. I realize I should probably know this, but I'm not exactly car savvy and it's been a while since I last needed a jump. :o)|||Impossible to say did the battery go dead by you leaving your lights on? If so you should be Ok. If not the battery may be dieing or your cars alternator may be going out and not charging the battery properly. I would take the car by a parts place and let them check your charging system most will do it for free and will tell you if you have a problem. Good Luck|||Once you jump your car try to let it run for a little while so that your alternator can charge it up. after 3 years your battery is probably still good. my last one i replaced lasted for 10 years but it all depends on the type of battery too. If your car starts to always have a dead battery it could either be your battery is no longer holding charge or you need to have someone look at your alternator to see if it is charging the battery like it should be.|||it depends on why you needed a jump. if it was because you left your headlights on or an accessory plugged in, then your battery is fine. if it wasnt, something may be wrong with your charging system. my suggestion would be to keep going, you're fine as long as your alternator is working and your charging system runs good. if it happens again soon, then have it looked at... meanwhile keep a set of jumper cables in your car in case it does happen so anyone can help you... hope this helps... drive safe|||Well, if your in the arctic....You should have it "load tested" it will give you the condition of battery. It could be dirty cables, bad altenator or battery. where I live it is often sub zero in morning and this is hard even on new battery. Oh, check water in battery cells also, even though they are semi sealed, sometimes adding distilled water helps.