I'm blunt and concise.

"I have been an atheist since age 13, when I realized the Bible is just a book of stories written by men."

Favorite smart-aleck replies-

"I don't believe in an invisible being that resides somewhere beyond the clouds."

"I chose rational thought, not magical beliefs."

"I stopped having imaginary friends at age four."

One of my favourites is quoting Douglas Adams: Isn't it enough to see that a garden is beautiful without having to believe that there are fairies at the bottom of it too?

Me : I don't believe I Jesus. do you believe in dragons ?
Them : dragons aren't real.
Me : exactly how I feel about your god.

Perhaps just smile and say an agnostic doesn't have a need for Jesus, but yes there are a lot of men called Jesus in South America and a lot of women would believe in them. See how that goes down. They just want to convert you or start an argument.

As Carl Sagan said: "I don't want to believe, I want to know".

At my previous workplace I was asked about that several times and I kept deflecting until I had had enough... I finally said, "Why do you keep asking me this? Are you in a cult or something?! Is this something sort of weird recruitment ritual of yours that you have to keep browbeating me about this? Have you met Ms. ...... in HR? I bet she would love to hear you ask her this same question over and over!"

The shocked look on her face was so satisfying... She never asked me again but she also never spoke to me again.

Double win!

BTW- I live in MI and some of these Christians are relentless... I have 2 friends I've known since high school who are deeply religious. I came out to them around 1985... They tried their best to convert me to no end.

Since then we are simply friends and they never bother me about it.

Response: Do you believe in Santa Clause, the Tooth Fairy, Leprechauns?

Alternately: I have been saved . . (a short hesitation) . . . . from Christianity!

The situation reminds me of being pulled-over by a cop when you know your rights, but it's just not going to help you to tell the cop your rights. I like your simple response: "I'm at work".

Question: Do you believe in Jesus?
Response: You mean my sister's boyfriend? Yah, he's a trustworty guy.

Question: Do you believe in Jesus?
Response: Jesus who?

Question: Do you believe in Jesus?
Response: Depends on how many martinis I've had.

Question: Do you believe in Jesus?
Response: Is he the guy who hangs out at the North Pole?

Tell them you believe "Jesus" was right about religion being a private matter.
Matthew 6. 5
"And when you pray, do not be like the hypocrites, for they love to pray standing in the synagogues and on the street corners to be seen by men."

Sometimes it's easier to use their faith against them.

Yes, he lives down the street from me. I believe his name is pronounced "hey-sus," though.

On the nowadays very rare occasions when I get accosted by the odd annoying Xrstian ( Faithfool) I usually respond with, " Jesus, you mean the real FIRST ever fan of the Nine Inch Nails, is that the bloke your talking about?"
Their reactions ARE truly priceless and YES, I am a very 'out there' Atheist.

Are these coworkers asking? Or people in the general public?

Depending upon who is asking, I’ll usually just say I’m not religious....it’s less scandalous than outright saying you’re atheist. That being said, I’m pretty open about being a heathen so unless I’m concerned that it could affect how I’m treated at work or something along those lines, then I’ll just say either I don’t believe in god or that I’m atheist.

At one of my jobs I had 3 closeted atheists confess they are too but “can’t” out themselves. Usually for familial reasons

Just wink at them and say, "I believe in YOU!"

Then walk away!

Religious people are simply people who are deluded into believing the unbelievable, so treat them gently. They are, in a sense, mentally ill because they believe there is another world out there somewhere. They are best ignored because it is a waste of time because whatever you say they sweep it away with their broom of faith. GROG

I deal with this daily at my hospital job. It's frustrating but I have to remind myself that many people there are in fear and looking for comfort or solace.

I do not shy from answering though, as my entire staff knows my beliefs and that if they are going to talk about theirs I will talk about mine.

I don't have to deal with it any more. I guess my beliefs are pretty clear. The other day a younger woman approached me after a coworker shared her beliefs. The younger woman whispered to me that she doesn't believe either. When I pointed out that I didn't say that I don't. She laughed and replied, "You didn't have to say anything."

My response will depend on the person asking. If it is a young physically healthy assertive person I switch into a rather happy (big smile) mode and confidently respond along the lines of: "I believe in Jesus like I believe in Voldemort, they both exist as fictional storybook character with supernatural i.e. MAGIC powers. The common response from them is often something along the lines of - "Oh you must be an atheist. That means you don't believe in anything." I love this assertion as I get to correct them with, "On the contrary, believe in things that can be demonstrated. I simply have a higher standard for truth then theists. Religion is based on faith asserted as truth. I don't accept faith (claims asserted as truth without supporting evidence) as demonstrably true (thing that can be demonstrated) as this is dishonest and I will not lower my standards for truth to accommodate ridiculous faith based fact-free claims as having testable merit. - - they usually run away after that response but occasionally come back a few days later for another round where I get to knock them around some more. . . .

Not so much at work, but my response to those wonderful people (smirk) who show up on my doorstep on Saturday mornings is to tell them that I agree with Reza Aslan that there probably was such a person, but that, given the 2000+ years since he supposedly lived, his narrative has been subject to significant fluctuations and likely bears no resemblance to the many versions currently attributed to him. One example to demonstrate difficulty in communications is the telephone game, in which participants are instructed to relate a story through a sequence of individuals. As it gets passed from individual to individual, the story usually gets pieces added and dropped. When I've seen this exercise performed, it rarely exceeds 30 people and is pretty well mangled by the end. Now, imagine that story passed from person to person over the course of 2000 years and how many people? By the time anyone thinks to start writing things down, how much would you expect it to remain consistent with the original version? Thomas Paine wrote Age of Reason over 200 years ago and even then, he was recognizing inconsistencies within the bible and what a mish mash of random pieces it represented. So, sure Jesus probably existed, as did Hammurabi and Genghis Khan, but once you start deciding what their thoughts were about various topics, you start venturing into speculation, lore and fantasy; you've lost site of facts.

I just say "no".

If you really want to be polite, be honest. I would give them a brief answer. "I'm evidence based. Not faith based." But I've been "out of the closet" for some time.

I would counter the question with some snarky question like do you believe in Quasi Moto?

Luckily I work with dogs. All they ask me is, "Do you have treats?" I rarely come across situations where people might ask me if I believe in Jesus, thank Dog. Religion is a subject rarely discussed. If asked, I usually just answer straight NO and leave it at that. If they don't want to leave it alone and start an argument, then they will get the whole works from me.

And.....that's why I wear this!:

For a long time now I have given the same answer as I give un-solicited salespeople........."no, and I'm not interested".....most often gets the job done, without comming off as confrontational..