How to Sign “Fast” in ASL – Baby Sign Language Guide

Learn the ASL sign for "fast" — Flick both thumbs forward from a fist. Visual diagrams, when to use it, and toddler-friendly versions.

BABY SIGN LANGUAGE • FEELINGS
Descriptor sign

FAST

Flick both thumbs forward from a fist

zoom! Flick both thumbs forward from a fist Like a quick zoom
DIFFICULTY
Moderate

TYPICAL AGE
14–20 months

HANDS
Two

MOVEMENT
Thumbs flick

How to Sign “Fast” Step by Step

The ASL sign for fast flick both thumbs forward from a fist — like a quick zoom.

1

Set your hands

Like a quick zoom. Get your hands into position before starting the motion.

2

Begin the motion

Flick both thumbs forward from a fist.

3

Repeat twice

Repeat the motion two times so the sign reads clearly. That’s fast.

Memory trick for parents: Picture the motion: like a quick zoom. The mime is the meaning.

When to Use the Sign for “Fast” With Your Baby

Use the sign for fast naturally throughout the day:

  • During the moments when fast comes up in your routine
  • When reading books that feature fast
  • Pair with more and please for early sentences

What Your Toddler’s Version Will Look Like

Expect a friendly approximation at first — refinement comes with practice:

  • A simplified one-handed version of the motion
  • Pointing at the thing and looking at you
  • A baby-babble approximation of “fast”

If the gesture is consistent and means “fast”, honor it — respond as if they said the word. The tidy adult version comes later.

Mistakes to avoid when modeling the sign

  • Don’t rush the motion — pause for eye contact before signing.
  • Keep the handshape consistent so baby can copy it.
  • Always say the word out loud while you sign — the pairing is what teaches.

Signs to Learn Next

Frequently Asked Questions

When can my baby copy the sign for fast?

Most babies begin approximating this sign around 14–20 months. Honor any clear approximation as a real attempt.

What if my toddler uses a simpler version of fast?

That’s exactly what you want at first — respond as if they signed it perfectly. The adult form will refine on its own with steady modeling.