Businessman grinning and giving a thumbs-up gesture.

If someone’s ever sent you “FS” in response to your messages, you should consider it a good sign. Here’s what this initialism means and how to use it in your texts.

For Sure

FS can mean a few things, but it most commonly means “for sure.” It’s an initialism that essentially means “definitely” — positively responding to someone’s question or emphatically stating your thoughts. For example, if someone asks whether you’re going to a party next weekend, you might say, “FS, I wouldn’t miss it.” You can also say, “I think the Bucks are winning, FS,” to emphasize how strongly you believe in a sports opinion.

This initialism can be written in both the uppercase “FS” and the lowercase “fs,” however, the lowercase version is much more common nowadays. You might accidentally confuse this with some similar-looking acronyms like “FFS,” which stands for “for fuck’s sake.” There’s also “fr,” meaning “for real.” FS and FR can have similar definitions depending on what kind of context you use them in.

The Origin of FS

Unlike other acronyms that we’ve covered, FS is a relatively recent creation. It can be traced back to the mid-2010s, with the rise of direct messaging apps such as Snapchat, WhatsApp, and Instagram DMs. The first definition for FS as “for sure” on the internet slang repository Urban Dictionary dates back to 2016 and simply reads, “for sure.”

It’s part of a recent phenomenon of extremely short acronyms that rose to popularity in the 2010s, along with terms like NP and BB. With most of our internet interactions taking place on phones, people are always looking for ways to save an additional keystroke when writing messages. Of course, it helps that FS is a versatile acronym that you can deploy in various situations, from confirming plans with a friend to emphatically stating your opinion.

Nowadays, you’ll mostly find FS in private messages between friends. However, you can also find it in community-based online chatrooms such as Discord and social media platforms like Twitter and Instagram.

RELATED: What Does "BB" Mean, and How Do I Use It?

Enthusiastic Agreement

People mostly use FS in two ways: either as a standalone reply or to emphasize the rest of the message.

On its own, you can use “FS” to agree with someone strongly. When someone tells you, “We should hang out sometime,” you can say “fs” to say that you want to spend more time with them. You can also use it to support someone else’s opinion. For example, if your friend says, “I think the rain sucks,” you can reply with “FS” to corroborate their hatred of the weather.

You can also attach it to the end of a message to provide assurance or convey your point more strongly. If you’re sending out a message trying to convince your friends to see a play with you, you might say, “This play will be so good, fs.”

Other FS Definitions

A home real estate "For Sale" sign in front of a house.
Andy Dean Photography/

Aside from “for sure,” there are a few other FS initialisms that you’ll find on the internet. The most common among these is “For Sale,” a term typically used in online marketplaces and e-commerce spaces. This is especially common for listings where it’s not immediately evident if someone wants to buy, sell, or rent something out. For example, in real estate listings, people often need to clarify that a house is “for sale” or FS, in contrast to other properties that people can lease.

It’s unlikely that you’ll confuse “for sure” and “for sale.” These two definitions appear in wildly different contexts, with “for sure” mostly living in personal conversations and “for sale” in buy and sell spaces like Facebook Marketplace.

Some less common definitions for FS include “file system,” which is the infrastructure of different files on a computer. In some countries, FS can stand for “foot-second,” an indicator of speed that describes how many feet can be covered in a second. Among gamers, FS can also mean “flight simulator,” a game genre that simulates complex flight dynamics in realistic environments.

RELATED: Why You Should Play Microsoft Flight Simulator 2020 for Xbox

How to Use FS

Using FS is relatively straightforward. You can use it as a reply to agree with something or as a modifier to make your messages more emphatic. However, avoid using it in the workplace since this is a casual slang term.

Here are a few ways to use FS:

  • “Oh, yes, FS. I’d love to go out of town.”
  • “This restaurant is going to be incredible fs.”
  • “We’re going to be a great time, fs.”

Are you interested in learning other online slang terms? Then, check out our explainers on NR, NVM, and OP. You’ll be texting like an internet expert in no time!

RELATED: What Does "OP" Mean Online, and How Do You Use It?

Profile Photo for Vann Vicente Vann Vicente
Vann Vicente has been a technology writer for four years, with a focus on explainers geared towards average consumers. He also works as a digital marketer for a regional e-commerce website. He's invested in internet culture, social media, and how people interact with the web.
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