Looking for a new job can easily become a full-time job itself. Between tweaking your resume, writing cover letters, and going on interviews, you're apt to sink a ton of time and mental energy into the process -- so that when you find yourself actually getting an offer, your first inclination might be to jump for joy and say yes.

Don't do it.

Well, you can jump for joy, at least in the privacy of your own home or somewhere your prospective employer can't see you. But when you're faced with that offer -- which you'll most likely get over the phone, because that's how companies typically roll -- your best bet is to play it cool and ask for some time to think it over. Otherwise, you could risk selling yourself short.

Professional extending a handshake

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The dangers of jumping on a job offer

On the one hand, accepting a job offer on the spot is a good way to kick off your relationship with your potential employer. Say yes right away, and your employer will know you're excited about the opportunity.

On the other hand, accepting an offer immediately could come back to haunt you. For one thing, the salary you're being offered might seem reasonable, especially if you're new to the workforce or your particular field. But before you say yes, you should take the time to make sure that number is really fair. For example, maybe most of the people you know with similar roles are making roughly the same as that number your prospective employer threw out. But what about the general population?

Though you might think you know what sort of salary is competitive, a better bet is to do your research before saying yes. Job site Glassdoor has a particularly valuable "Know Your Worth" tool that lets you compare salaries by job title and geographic region, so you can use it to see how your offer stacks up.

Another factor you'll want to consider is how your potential employer plans to compensate you outside of just salary. Benefits play a huge role in employee satisfaction, so if you're looking at a stingy vacation policy and poor health coverage, those are points to come back and negotiate on. Though you probably won't get an employer to change its time off policy just to seal the deal, what you might get is a bit more money in exchange for lackluster benefits.

And the opposite holds true, too. If your salary isn't great but your benefits are fabulous, you might choose to move forward. The point, however, is that you need time to make that decision, which is why you shouldn't jump to accept an offer right away.

When the pressure is on

So what happens when you're given an offer and are asked to respond immediately? Request a minimum of 24 hours to make your decision (and yes, that's a minimum, folks -- you have every right to want several days). Explain to your prospective employer that while you appreciate the offer, you want to take the time to make sure the role is a good fit.

If you're pressured to decide sooner, then you may want to err on the side of saying no. After all, accepting a job is a huge decision, and it's one that has consequences not just for you, but for your employer, as well. Therefore, if a company can't agree to a 24-hour time frame for a response, it could be a sign that such unreasonable behavior is typical of that employer. And that's not something you want to sign up for.

Much of the time, however, you will be given a decent window to mull over an offer, so take that opportunity rather than rush to say yes. Otherwise, what you think is a great decision could be one you quickly come to regret.