"Tired" means exhausted (physically or mentally); "sleepy" means wanting to sleep specifically.
Exhausted, worn out. Can be physical (after exercise) or mental (after lots of work). Does not necessarily imply wanting to sleep.
I am so tired after that hike. My legs feel like jelly.
Estoy tan cansado despues de esa caminata. Mis piernas se sienten como gelatina.
She is tired of waiting. She has been here for two hours.
Ella esta cansada de esperar. Ha estado aqui dos horas.
He looked tired after the long flight across the Atlantic.
El lucia cansado despues del largo vuelo transatlantico.
Drowsy. You feel like you are about to fall asleep. You want to sleep right now.
I am so sleepy. I could fall asleep right here at my desk.
Tengo tanto sueno. Podria quedarme dormido aqui mismo en mi escritorio.
The warm room and the boring lecture made everyone sleepy.
El cuarto calido y la aburrida conferencia dejaron a todos con sueno.
She gets sleepy right after lunch every day. It is like clockwork.
A ella le da sueno justo despues del almuerzo todos los dias. Es como un reloj.
Common mistake
Saying "I am very tired" when you mean you feel sleepy (you want to sleep). You can be "tired" (exhausted) without being "sleepy": after running you are tired but maybe not sleepy. And you can be "sleepy" without being "tired": if you take a medication that causes drowsiness, you are sleepy but not physically exhausted. In Spanish "cansado" covers both, but in English they are different words.
Trick to remember it
Question: could you fall asleep right now? If yes: "sleepy". Are you exhausted but not necessarily about to sleep? "Tired". The phrase "I'm tired of..." (I'm fed up with...) only works with "tired", never with "sleepy": "I'm sleepy of this" does not exist.
Quick rule
Tired = exhausted (fatigue). Sleepy = drowsy (I want to sleep right now).
Did you know?
"Sleepy" is also the name of one of Snow White's seven dwarfs in the original English version. The seven dwarfs are named after moods or traits: Happy, Grumpy, Sleepy, Bashful, Sneezy, Dopey, Doc. In Spanish they were creatively translated: Dormilon, Gruñon, Feliz, Timido, Estornudo, Tontito, Sabio.
Exercise 1 · Pick the right one
After eight hours of coding, she was completely _____ and needed a break.
Exercise 2 · Pick the right one
The long car ride made the children _____ and they fell asleep within minutes.
Exercise 3 · Form the word
Tired = exhausted (fatigue). Sleepy = drowsy (I want to sleep right now).
Saying "I am very tired" when you mean you feel sleepy (you want to sleep). You can be "tired" (exhausted) without being "sleepy": after running you are tired but maybe not sleepy. And you can be "sleepy" without being "tired": if you take a medication that causes drowsiness, you are sleepy but not physically exhausted. In Spanish "cansado" covers both, but in English they are different words.
Question: could you fall asleep right now? If yes: "sleepy". Are you exhausted but not necessarily about to sleep? "Tired". The phrase "I'm tired of..." (I'm fed up with...) only works with "tired", never with "sleepy": "I'm sleepy of this" does not exist.
Bryan López
Founder of SpeakUP Academy