Speech milestones by age, from first sounds to sentences

Speech is the milestone parents compare most and understand least, because the visible part — words coming out — is the last step in a process that has been running for a year. By the time a child says something, they have already sorted out that sounds carry meaning, that conversation takes turns, and that objects have names.

Which is why the single most useful question is not how many words. It is whether they understand you.

Understanding comes before talking

Receptive language — what a child takes in — runs months ahead of expressive language for every child. A one-year-old typically understands dozens of words and says one or two. That gap is normal and it is the thing to check when speech seems slow.

You can test comprehension without any special setup. Ask for something without gesturing or looking at it: “where is your shoe?” with your hands still and your eyes on the child. If they find it, comprehension is intact.

Speech milestones by age

These follow the revised CDC checklists, which describe what most children can do rather than the average — so a child meeting them is comfortably typical, and one missing them is worth a conversation.

The 50-word figure is worth a note, because you will see it attached to two different ages. Older guidance placed it at 24 months; the CDC’s 2022 revision moved it to 30 months, so a wider band of typical children meet it. If you have read both and worried, that is why.

How much should a stranger understand

Intelligibility is a more useful measure than vocabulary from about two onwards, and it has a clean rule of thumb. Roughly:

• At 2 years — about half of what they say is understandable to someone outside the family
• At 3 years — about three quarters
• At 4 years — essentially all of it, even if some sounds are still wrong

Individual sounds arrive late and that is fine. R, th, l and s commonly stay imperfect until five or later. The concern is not a mispronounced sound; it is a four-year-old whose sentences a stranger cannot follow.

What counts as a word

More generously than parents assume, which matters when you are trying to work out whether a child is behind.

• Consistency is the test, not accuracy. “Nana” for banana every time is a word.
• Animal sounds count at this stage — “moo” used to mean cow is a word.
• Signs count if a child uses them meaningfully, and signing does not slow speech down.
• Words in any language count, and they add together rather than competing.
• Babbling does not count. “Dada” said to the dog, the door and the dinner is practice, not a word.

Bilingual households are not a delay

This gets blamed for slow speech more than anything else, and it should not be. Bilingual children hit the same milestones at the same ages when you count vocabulary across both languages together.

What is genuinely normal in a bilingual child:

• Mixing both languages in one sentence — a sign of competence, not confusion
• A smaller vocabulary in each language separately, with a normal combined total
• A stronger language that switches depending on nursery, holidays or who visits
• A silent period of several weeks after a new language is introduced

The advice that used to circulate — drop one language if speech is slow — is not supported and costs the child a language for nothing. If a bilingual child has a genuine delay, they will have it in both languages, and an assessment should look at both.

What actually helps language develop

Language is built from turn-taking with a responsive person. Everything below is a version of that.

Things that work

• Narrate what you are doing. Ordinary commentary during nappies, cooking and the walk to the shops is the bulk of a child’s input.
• Wait after you ask. Five full seconds. Most adults give under one, and the pause is where the child’s turn was meant to go.
• Expand rather than correct. “Doggy!” becomes “yes, a big brown doggy” — not “say dog”.
• Read the same book repeatedly and let them fill in the line they know. Repetition is the point, however tired of it you are.
• Get down to their eye level so they can see your mouth making the sound.
• Offer choices out loud — “apple or banana?” — which creates a reason to produce a word rather than a point.

Things that do not

• Anticipating every need, which removes the reason to ask
• Making a child perform words for other adults
• Correcting pronunciation directly, which mostly reduces attempts
• Educational video for under-twos, which does not transfer to real language
• Older siblings answering on their behalf, which is well meant and very effective at delaying the need to speak

Late talker or language delay

“Late talker” describes a child with normal comprehension, normal play, normal gestures and few words. Many resolve without intervention. But you cannot reliably tell in advance which ones will, and the cost of assessing a child who turns out to be fine is essentially nothing.

These raise the priority:

• Comprehension that also seems behind
• Few gestures — no pointing, waving or showing you things by 12 to 15 months
• Little interest in interaction, or no response to their name
• Repeated ear infections or glue ear, which is a very common and very fixable cause
• A family history of speech or language difficulty
• Any loss of words or skills previously present

Hearing is the first thing to check in every case. A child who is not hearing clearly cannot learn to speak clearly, and intermittent hearing loss from fluid in the ears is easy to miss precisely because it comes and goes.

When to ask for an assessment

Ask your health visitor, GP or paediatrician for a referral if there is no babbling by 12 months, no words by 16 months, no two-word phrases by 24 months, speech that strangers cannot understand at all by 3 years, or any loss of speech or social skills at any age. Regression is the one that should never be watched and waited on.

You do not need permission to be concerned and you do not need to wait for a professional to raise it first. Speech and language therapy is most effective early, and no assessment has ever harmed a child who turned out to be fine.