Language development 0–12 months: from cooing to first words

Language development doesn't start at the first word. It starts in the womb, where babies begin detecting the rhythms and sounds of the language around them. By birth, newborns already show a preference for their mother's voice and recognise familiar sounds from their prenatal environment.¹ Everything from birth to those first real words is building the foundation for speech.

The timeline: what to expect and when

0–2 months: cries and early vocalisations

Crying is communication. Newborns quickly develop different cry patterns for hunger, discomfort, and tiredness — and experienced caregivers get surprisingly good at reading the differences.

Around 6–8 weeks, most babies begin cooing — soft, vowel-like sounds ("ooh", "aah") made during alert, happy states, usually in response to a face or voice. Cooing is the first deliberately social vocalisation. It is not random. Babies coo at people.

2–4 months: back-and-forth

Cooing becomes more varied, and babies begin genuine conversational turn-taking — you speak, they respond with sounds, you respond, they respond. This proto-conversation is developing the architecture of real conversation: it has turns, pauses, and responses.

Laughter arrives around 3–4 months in most babies — a social reward that reinforces the interaction.²

4–6 months: early babbling

Vowel sounds become more varied. Babies start experimenting with sounds made at the front of the mouth — raspberries, squealing, and early consonant attempts. This is the beginning of canonical babbling.

6–9 months: consonant-vowel babbling

Between 6 and 9 months, most babies begin repeating consonant-vowel combinations: "ba-ba-ba", "da-da-da", "ma-ma-ma". This reduplicated babbling is a significant milestone — it requires much more precise motor control of the lips, tongue, and jaw than earlier vocalisations.¹²

By 9 months, babbling becomes more varied — mixing consonants, varying rhythm and intonation, sounding increasingly speech-like even though the words aren't there yet. This is called variegated babbling.

9–12 months: words on the way

In the months before the first real word, language comprehension accelerates dramatically:

• Responds to their name (typically by 6–9 months, reliably by 12 months)
• Understands "no" and a few other familiar words
• Follows simple instructions with a gesture ("give me the cup" paired with an outstretched hand)
• Points — first to request something, then to share interesting things

First true words — sounds or approximations used consistently to refer to specific things or people — typically emerge between 10 and 14 months.² A "word" at this stage doesn't have to sound like the adult version. "Ba" said consistently when reaching for a ball counts.

By 12 months, most babies have 1–3 words. Some have more, some have fewer and are still developing typically.

Receptive vs expressive language: why the gap matters

Receptive language is what a baby understands. Expressive language is what a baby produces. Receptive language always leads expressive language — typically by weeks to months.

A baby who understands their name, "no", "more", and several object names but isn't yet saying words is using receptive language appropriately. The absence of expressive words alone is not automatically a red flag if receptive language is developing well.³

This distinction matters when evaluating language development. Asking "does my baby understand?" is as important as asking "does my baby talk?"

Why talking to your baby is the most effective intervention

Research on language outcomes consistently identifies one factor above all others: the volume and quality of language input a baby receives. The landmark Hart and Risley study found that by age 3, there was a 30-million-word gap between children from language-rich and language-poor environments — and that this gap strongly predicted school outcomes.⁴

More recent research has refined this: it's not just quantity but conversational turns — back-and-forth exchanges where the adult responds to the baby's sounds and the baby responds back — that predict language outcomes most strongly.⁴

What this means in practice:

• Narrate your day. "I'm putting on your left sock. Now the right one."
• Respond to babbling as if it's a conversation. Baby says "ba-ba", you say "yes, that's your bottle."
• Read aloud. At any age. The story matters less than the rhythm, vocabulary, and shared attention.
• Avoid back-to-back passive screen time, which doesn't provide conversational turns.

You don't need to perform this. It happens naturally if you're simply talking to and with your baby throughout the day.

Bilingual exposure

Babies raised in bilingual or multilingual households meet language milestones on the same overall schedule as monolingual peers. They may have slightly fewer words in each individual language but have equivalent or greater total vocabulary across both languages combined.³

Bilingual babies may code-switch — mixing words from both languages in the same utterance — which is normal and not a sign of confusion. They're not learning two separate languages; they're learning one integrated communication system with two vocabularies.

Exposing a baby to two or more languages from birth does not delay language development. This is well-established and consistent across populations and language pairings.³

← Back to the complete guide: Baby development from 0 to 24 months

Also in this cluster: Social smiles and attachment · Play by age and stage

Sources

1. Centers for Disease Control and Prevention. "Developmental Milestones." CDC Learn the Signs. Act Early., 2022. https://www.cdc.gov/ncbddd/actearly/milestones/index.html
2. NHS. "Your baby's development." NHS, 2023. https://www.nhs.uk/conditions/baby/babys-development/
3. American Academy of Pediatrics. "Language Development: 8 to 12 Months." healthychildren.org, 2023. https://www.healthychildren.org/English/ages-stages/baby/Pages/Language-Development-8-to-12-Months.aspx
4. American Academy of Pediatrics. "Language Delays in Toddlers: Information for Parents." healthychildren.org, 2023. https://www.healthychildren.org/English/ages-stages/toddler/Pages/Language-Delay.aspx