Is It Correct to Say “Time Flies by So Fast”?

You already know that “time flies by so fast.” It moves quickly, and you need to keep on top of it before you miss out on the things you love.

The phrase works well, but is it correct? That’s why you’re here, and that’s why we’ll answer that question (and more).

Is It Correct to Say “Time Flies by So Fast”?

“Time flies by so fast” is grammatically correct. It’s an idiomatic expression showing that time passes so quickly it’s almost impossible to notice. It reminds people to make the most of their time. Before they know it, it could all be over, so you need to enjoy the passage of time while you can.

The phrase looks a bit strange at first glance but fear not; it is correct English.

• Time flies by so fast. There really is no way for us to know when it’ll all be over.
• They say that time flies by so fast, but I don’t know what to do with that information.

“Time flies by so fast” works well because it shows that time passes quickly. “Flies by” suggests that time keeps moving and doesn’t wait for anyone.

You may also hear “time flies so fast,” where “by” is dropped from the expression. This also works, but removing “by” makes it a little less impactful. Instead, it just suggests that time goes quickly rather than it “passing by” you.

Including “by” shows that time is outside your control. It’s better to remind people to seize the day.

We’ve not shown you that “time flies by so fast” is indeed correct to use. If you’re not all that comfortable using it, you might benefit from a few alternatives that work well. We’ve gathered some of the best suggestions on what to say instead of “time flies by so fast.” Check them out in the next section.

Other Ways to Say “Time Flies by So Fast”

Other ways to say “time flies by so fast” are “time waits for no one,” “time moves quickly,” and “time flies.” These phrases are great idiomatic expressions. They show that time moves rapidly, often meaning that people will miss out on the best things in life.

1. Time Waits for No One

“Time waits for no one” is a great idiom that works well. It is another way to say “time flies by so fast” because it suggests that time will not “wait” for anybody (no matter who you are or how important you might be).

“Time” isn’t a person, but you can use personification to treat it as such and show that the verb “waits” applies when reminding someone of how quickly time moves. “Waits” implies that time actively chooses to wait (or not wait, in this instance).

• Time waits for no one, Sam. If you don’t get out there and do something now, you may never get another chance.
• Time waits for no one. Why do you think we’ve come this far? Surely, you must know that things are going to keep changing.

2. Time Moves Quickly

“Time moves quickly” is a fairly simple idiom that doesn’t require much explanation. The words used are all self-explanatory, making it a simple choice for how to say “time flies by so fast.”

“Moves” replaces “flies by,” and “quickly” replaces “fast.” You must use the adverbial form “quickly” rather than “quick” in this phrase. “Quickly” modifies “moves,” demonstrating that time moves too quickly for people to keep up with.

• Time moves quickly, and you need to seize the day while you can. You never know what day will be your last.
• I know time moves quickly, but I still want to try and do these things. Do you think you could help me out?

3. Time Flies

“Time flies” is a very popular idiom used by native English speakers. The longer idiom is “time flies when you’re having fun,” though you don’t have to include the second portion of the phrase when demonstrating that time moves too quickly to keep up with.

“Time flies” suggests that time has a mind of its own. “Flies” shows the speed at which time travels, meaning it will happily leave you behind if you allow opportunities to get away from you.

This phrase uses personification again to show that “time” is somewhat selfish. It does not wait around, and it keeps moving.

• Time flies, Mathew. You can’t keep thinking that something good will come your way. You have to work for these things.
• I can’t believe it’s been thirteen years since we last saw each other! That’s crazy! Time flies, doesn’t it?

4. You Might Get Left Behind

“You might get left behind” is a great idiomatic expression used as another way to say “time flies by so fast.” You can use this to remind people that time doesn’t wait around, and it will happily leave someone behind if they get too caught up in it.

If someone tends to dwell on the past or worry about the future, they might forget to live in the moment. This expression is for the people who struggle to live in the present. It reminds them not to get left behind and to enjoy life as it unfolds around them.

• You might get left behind if you’re not careful. Remember, time waits for nobody, and you’ll figure that out soon.
• You might get left behind, man. I don’t want that to happen to you. Seize the opportunity when it next comes your way.

5. Time is a Fickle Thing

“Time is a fickle thing” means that time constantly changes, and you can never tell what you will get out of it. This encourages people to enjoy the time in their life because they never know when the best and worst opportunities will present themselves.

“Fickle” means ever-changing. You should use it because time is prone to change as life goes on. It’s not easy to settle into a consistent routine or rhythm because life and time often find ways to mess those up for people.

• Time is a fickle thing. Some days it feels slow. Other days it’s way too fast. You’ve got to understand that about the world.
• I get that time is a fickle thing, but I still want to make the most of the time I have here. Does that make sense to you?

6. We Only Have So Much Time

“We only have so much time” works well as one of the alternatives here. It is a fairly morbid phrase reminding people that we don’t have long to live our lives, so we better make the most of the time we have.

While it doesn’t directly say “you will die one day,” it is implied through the meaning. It reminds people to seize life and enjoy the time while they can. After all, you can never be sure when your last day might be.

• We only have so much time to make the most of our lives. We can’t keep waiting until something good comes our way.
• We only have so much time. Please, stop wasting it doing these things that don’t matter in the long run.

7. Enjoy Your Time While You Can

“Enjoy your time while you can” shows that time is limited and can move quickly. It reminds someone to make the most of their time because they never know what day will end up being their last.

While it might sound like a morbid expression, it’s very effective when you want to inspire someone. It lets them know that they have a life to live, and they should do everything they can to try and enjoy it or make the most out of it.

• Enjoy your time while you can. It can be taken away from you in a moment. I don’t want that to happen.
• Enjoy your time while you can, Sarah. I will not be here forever to give you the guidance you need.

8. Don’t Blink, or You’ll Miss It

“Don’t blink, or you’ll miss it” is a great expression to use. “It” refers to time, and you can say this to remind people that they have to take in every moment because they might “miss” the best bits of their life. “Blink” is used as a synonym for missing an opportunity in life here.

It might help to break the phrase down further.

“Don’t blink” reminds someone to take every moment as it comes. It lets people know they need to make the most of their time and the opportunities that present themselves while they live.

“You’ll miss it” reminds someone that these opportunities only last for a brief period. Before long, they’re gone again, and it’s all too easy for someone to “miss” them.

• Remember, don’t blink, or you’ll miss it. You might lose some of the best opportunities because you waited too long.
• Don’t blink, or you’ll miss it. I can’t stress that enough. I regret missing out on all the opportunities in my life.

9. Don’t Forget to Take it In

“Don’t forget to take it in” is a great idiom used as a synonym here. It suggests that people can often forget to enjoy their life or make the most of their time. “Don’t forget” is a good reminder to let people know there are still plenty of things to enjoy.

This works well when you’re worried about someone taking their life for granted. It lets them know that they still have so much left to enjoy. They simply need to find the beauty in the things around them right now and not “forget” to take it all in.

• Don’t forget to take it in as you can. There’s so much happening in your life. Enjoy it while it’s there.
• Don’t forget to take it in, people. I know getting caught up in the moment can be easy, but time won’t wait for you.