Baby sign language is not the same as ASL. While many baby sign programs borrow individual hand shapes from American Sign Language, they strip away the grammar, sentence structure, and cultural context that make ASL a complete language. What parents typically teach their babies is a small collection of isolated signs, not a language system.
What Makes ASL a Full Language
American Sign Language has its own complex grammar, word order rules, and sentence-building conventions that are completely separate from English. It uses facial expressions, eyebrow movements, body positioning, and the directionality of hand movements to convey meaning. For example, signing HUNGRY in ASL involves raising your eyebrows and combining the sign with directional cues and pronouns to form a complete question: “HUNGRY? YOU? HUNGRY?” The way you move a sign like GIVE changes depending on who is giving and who is receiving. These grammatical layers are what make ASL a living, fully expressive language used by the Deaf community.
Baby sign language uses none of this. A parent signing “milk” or “more” to a baby is producing a single gesture in isolation, without syntax, without the grammatical markers that give ASL its structure. As the American Speech-Language-Hearing Association puts it, without ASL syntax, morphology, and pragmatics, these signs are simply symbolic gestures. Calling baby sign language a “language” is considered culturally inappropriate because it reduces a rich linguistic system to a handful of hand movements.
What Baby Sign Language Actually Is
Baby sign language is a communication tool, not a language. Parents learn a small set of signs for high-frequency concepts like “eat,” “more,” “all done,” “milk,” and “help,” then use them alongside spoken words during everyday routines. The goal is to give babies a way to express basic needs before their mouths and vocal cords are mature enough for speech.
Some programs pull their signs directly from ASL’s vocabulary. Others invent simplified gestures designed to be easier for small hands. Either way, the baby is learning individual symbols, not learning to construct sentences or engage in the kind of back-and-forth conversation that ASL supports. Think of it like teaching a baby to point at what they want: useful, but not a language.
Why Babies Can Sign Before They Can Talk
The reason baby signing works at all comes down to motor development. Babies gain control of their hands and arms months before they can coordinate the tiny muscles in their lips, tongue, and larynx needed for speech. Research tracking hearing children of Deaf parents found that babies produced their first recognizable sign at an average age of 8.5 months, with the earliest appearing at just 5.5 months. By comparison, most babies don’t say their first spoken word until around 12 months.
That gap of several months is the window baby sign language is designed to fill. Babies can understand far more than they can say, and giving them a physical way to express “milk” or “more” reduces the frustration of not being understood. In one study, babies whose parents encouraged symbolic gestures began using them about three weeks before their first spoken words, giving them a small but meaningful head start on two-way communication.
Does Signing Delay Speech?
This is the concern most parents have, and the research consistently points in the opposite direction. Babies who are taught signs do not show delayed speech. In fact, a study by Goodwyn, Acredolo, and Brown found that hearing infants whose parents encouraged symbolic gestures actually outperformed children whose parents focused only on encouraging vocal language on follow-up tests of both receptive and expressive spoken language.
The likely explanation is that signing doesn’t replace speech, it reinforces the underlying concept that things have names. Researchers who tracked babies from 11 to 24 months found that symbolic gestures and early words develop in tandem, and that the use of gestural labels was positively related to verbal vocabulary growth. In other words, babies who signed “dog” while learning the spoken word “dog” seemed to internalize the concept faster, not slower.
Most babies naturally phase out signing on their own. Research shows a surge in baby signing around 12 months, followed by a noticeable drop-off after 15 months as spoken words become easier and more efficient. This timeline lines up with the developmental stage where babies begin combining gestures with words, then move to two-word spoken phrases.
Why the Distinction Matters
For parents deciding whether to sign with their baby, the practical takeaway is straightforward: baby sign programs can be a helpful communication bridge during the pre-verbal months, and they don’t appear to slow down speech development. But it’s worth understanding that what you’re teaching your baby is a small set of borrowed gestures, not ASL itself.
This distinction matters to the Deaf community. ASL is a complete language with deep cultural significance, developed and maintained by Deaf people over generations. When baby sign programs market themselves as “teaching your baby ASL,” they can inadvertently trivialize the language by reducing it to a parenting trend. If you’re genuinely interested in your child learning ASL as a language, that requires learning its grammar, engaging with Deaf culture, and going far beyond the dozen signs most baby programs cover.
If your goal is simply to communicate with your pre-verbal baby, a handful of basic signs used consistently alongside spoken words can help. Babies as young as 6 months can begin recognizing signs, and most will start producing them somewhere between 8 and 10 months. You don’t need a formal program. Pick five or six signs tied to your daily routine, use them every time the situation comes up, and always say the word out loud at the same time. Your baby will let you know when they’re ready to drop the signs and just talk.