Learning how to sign understand in ASL gives your child a way to communicate before words arrive. “Understand” is the lightbulb moment captured in a single gesture. A pinched hand at the temple flicks the index finger up. Toddlers typically manage it between 18 and 24 months.
How to Sign “Understand” in ASL
Photos: Rodasmith via Wikimedia Commons, CC BY-SA 3.0
- Make the handshape: Pinch your index finger and thumb near your temple.
- Position at the temple: Hold the pinch close to the side of your forehead.
- Flick up: Snap the index finger upward, as if a light just switched on.
The flick is the moment of comprehension — the thought that was folded now opens.
Step-by-Step Photos
Photos: Rodasmith via Wikimedia Commons, CC BY-SA 3.0
When to Use It With Your Child
- At comprehension moments: “Oh! You understand!” when they follow a new direction.
- After re-explanation: “Now you understand?”
- Puzzle moments: Model it enthusiastically when they figure something out.
Tips for Success
- The pop of the finger matters — a slow uncurl reads as a different sign.
- Teach alongside “don’t understand” so toddlers can express both states.
- Model it with an “aha” expression for full effect.
Signs Related to “Understand”
“Don’t understand” (the same flick releasing from a pinch) and “know” (bent fingers tapping the forehead) are the conceptual family.
“Understand” is one of the most intuitively guessed ASL signs even by people who don’t know ASL.
Learn more: National Association of the Deaf — ASL resources and advocacy from the National Association of the Deaf.
Frequently Asked Questions
When should I start teaching my baby how to sign understand in ASL?
You can introduce the sign for understand as early as 18–24 months. Babies understand signs before they can produce them, so start modeling it consistently and reward any attempt — even an approximation — with the item or action right away.
How long does it take for a baby to learn to sign understand?
Most babies begin producing a recognizable version of the sign for understand within two to four weeks of consistent daily modeling. Frequency matters more than perfect form at this stage — sign it every time the word comes up naturally in your routine.
Is the ASL sign for understand the same in baby sign language programs?
Yes. Most baby sign language programs teach the authentic ASL sign for understand. Using real ASL rather than invented gestures means your child’s signs will be understood by Deaf signers and build a foundation for learning more ASL as they grow.