SquarePants is a cute sea sponge but he is drawn to resemble a kitchen sponge, being rectangular and bright yellow with a dark brown outline. In earlier episodes, he is wider near the top and gets skinnier going further down, but in more recent episodes, he is a more of a regular square shape. SpongeBob has large blue eyes, a long, slightly curved nose, a large mouth with two prominent front buck teeth, and dimples with three freckles on each cheek. He typically wears a white shirt with a red tie, black leather shoes with shoelaces, and brown rectangular pants with a black belt (the entire outfit is sometimes referred to as his "pants", hence his name). While working at the Krusty Krab, he wears a tall, white hat with a small blue anchor on it as a uniform. SpongeBob sometimes sleeps in his underwear, and at other times pajamas (beginning in Season 5). Though SpongeBob has always been voiced by Tom Kenny, his voice has changed over the course of the series; his voice is lower than normal in the pilot episode, and after the movie, his voice gets slightly higher-pitched. And also, SpongeBob never passed Boating School.
- Soft Pliable Body: Due to his soft, pliable frame, he is capable of shape shifting, has some degree of invulnerability, being able to absorb any type of physical impact, shown most notably in the episode, The Bully.
- Regeneration: It is shown that he can quickly regenerate parts of his body that are injured or removed.
- Boneless: SpongeBob is usually shown to be boneless (sea sponges being invertebrates) however in some episode like I Had an Accident are shown on its X-rays.
- Absorbent: Being a sponge, he is also absorbent, and can expand his body by absorbing liquids. When he cries, he often re-absorbs his tears. Such as in The Bully when Flats the Flounder kept on hitting him but Spongebob just absorbed all of his blows.
- Singing and Nose Playing: SpongeBob is shown to possess a fantastic singing voice. He uses his nose as a flute, which he is very good at. He was also the lead singer in Band Geeks.
- Fry-Cooking: SpongeBob has a job cooking Krabby patties at the Krusty Krab.
- Jellyfishing: SpongeBob and Patrick have jellyfished in several episodes, in Jellyfish Hunter, he caught every single jellyfish in the fields.
- Tongue-Boarding: SpongeBob tongue-boarded in Pre-Hibernation Week, he can also do it in the Battle for Bikini Bottom Video Game.
- Survival Skills: In To Save a Squirrel, SpongeBob and Patrick almost ate each other to survive.
- Bubble Blowing: SpongeBob can perform extraordinary moves with bubbles.
- "Today's the big day, Gary!" (first line, Help Wanted)
- "There it is. The finest eating establishment ever established for eating: The Krusty Krab, home of the Krabby Patty, with a Help Wanted sign on the window. I've waited years for this moment. I'm gonna go in there, march straight up to the manager, look at him straight in the eye, lay it on the line, and - I can't do this!" (Help Wanted)
- "Bring it around town!" (Bubblestand)
- It's all about finger strength, baby! (Pressure)
- "I'm readdddddddy!"
- "Order up!!!"
- "Tartar sauce!"
- "Ah, shrimp!"
- "Good morning world and all who inhabit it!" (Missing Identity)
- "The most important meal of the day, servin' it up, Gary's way!!" (Missing Identity)
- "Kare-a-tay!" (Karate Choppers)
- "Fish paste!" (Rock Bottom)
- "I'm ugly and I'm proud! (Something Smells)
- "Sandy, you may not have noticed, but I is 100% mam-male (Prehibernation Week)
- "Life is as extreme as you wanna make it." (Pre-Hibernation Week)
- "The Krabby Patty Secret Formula is the sole property of The Krusty Krab and is only to be discussed in part or in whole with its creator, Mr. Krabs. Duplication of this Formula is punishable by law. Restrictions apply. Results may vary." (Imitation Krabs)
- "If we're discussing the Secret Formula on the third Wednesday in January and it's not raining outside, after we gargle vanilla pudding, what do we do?" (Imitation Krabs)
- "What could be better than serving up smiles?" (Can You Spare a Dime?)
- "K-R-A-B-B-Y-P-A-T-T-Y says I!" (Fear of a Krabby Patty)
- "I gotta pinch myself because I must be dreaming. OOOOWW!!" (Fear of a Krabby Patty)
- "I'M READY TO PARTY!! ARE YOU READY TO PARTY!?" (Mid-Life Crustacean)
- "Cleanliness is next to managerliness." (The Spongebob Squarepants Movie)
- "You don't need a license to drive a sandwich." (The Spongebob Squarepants Movie)
- "I'm ready, promotion!" (The Spongebob Squarepants Movie)
- "I'm ready, depression." (The Spongebob Squarepants Movie)
- "Another Triple Gooberberry Sunrise, sir." (The SpongeBob SquarePants Movie)
- "Step aside, and you won't have to feel the awesome wrath of our mustaches!" (The SpongeBob SquarePants Movie)
- "I'm a Goofy Goober, yeah!" (The SpongeBob SquarePants Movie)
- "I'm a Goofy Goober, ROCK!!!" (The SpongeBob SquarePants Movie)
- "GARY!! YOU ARE GOING TO FINISH YOUR DESSERT AND YOU ARE GOING TO LIKE IT!!!" (Dying For Pie)
- "Well, it's no secret that the best thing about a secret is secretly telling someone your secret, thereby secretly adding another secret to their secret collection of secrets. Secretly." (The Secret Box).
- "I'm wearing three pairs of underwear right now!" (The Secret Box)
- "I have to skip town, start a new life, live under an assumed name! BobPants SpongeSquare! Yeah, that's good. Grow a beard and shave it off, and live happily ever after!" (The Bully)
- "Hey, you know, life's like a bucket of wood shavings, except for when the shavings are in a pail, then it's like a pail of wood shavings!" (The Bully)
- "Good afternoon, sir. Could we interest you in some chocolate?" (Chocolate With Nuts)
- "So, how long have you two ladies known each other?" (Chocolate With Nuts)
- "Let's change our names to 'Why' and 'Bother'." (Chocolate with Nuts)
- "No, let's save that for when we're selling real-estate" (Chocolate With Nuts)
- "I like Squidward…" (20,000 Patties Under the Sea)
- "Wanna see me run to that mountain and back?…Wanna see me do it again?" (Mermaid Man and Barnacle Boy V)
- "We've been smackledorfed!" (The Nasty Patty)
- "C-A-M-P-F-I-R-E-S-O-N-G SONG!" (The Camping Episode)
- "The world is your litter box!!!" (Dumped)
- "And you don't even need to use a bowlwlwlwlwlwl!!!" (Dumped)
- "Can I make a Krabby Patty now?" (Krusty Krab Training Video)
- "Remember that time that me and Sandy got married?" (Truth or Square)
- "Squidward, that wasn't the peace treaty, that was just a copy of the peace treaty." (Snowball Effect)
- "It matters not whether one is dirty or clean... for can cleanliness exist without filthiness? And would filthiness exist without cleanliness? (The Battle of Bikini Bottom)
- "If I have to memorize a single order I think I'm gonna explode!" (Squilliam Returns)
- "Airline food. My gosh, what is up with that stuff? Thank you, good night!" (Walking Small)
- "Wee-Snaw!" (My Pretty Seahorse)
- "Krabby The Clown is in the building!" (Krabby Land)
- "How could you, Mr. Krabs? You promised these children Krabby the Clown. But all I saw out there was *sniff* Cheapy the Cheapskate!" (Krabby Land)
- "I am now going to assault your mind with subliminal messages!" (Gary Takes a Bath)
- "It's the Best Day Ever!" (Best Day Ever)
- "Who put you on the planet? UGH!"