🍼 Adjusted (Corrected) Age Calculator
For babies born before 37 weeks, adjusted (or "corrected") age is commonly used instead of chronological age when tracking developmental milestones — this calculator computes both side by side.
For babies born before 37 weeks — adjusts age for prematurity.
How the Adjusted (Corrected) Age Calculator works
Adjusted age subtracts the number of weeks a baby was born early (relative to a full 40-week term) from their chronological age — commonly used through about age 2.
Step-by-step calculation
- 1Enter the birth date and weeks of pregnancy at birth.
- 2Weeks early = 40 − gestational weeks.
- 3Adjusted age = actual age − weeks early.
Worked example
A baby born at 32 weeks (8 weeks early) who is 26 weeks old has an adjusted age of 18 weeks — about 4 months.
Adjusted (Corrected) Age Calculator examples
| Gestational age at birth (weeks) | Chronological vs. Adjusted age |
|---|---|
| 24 | Chronological: 26 weeks · Adjusted: 10 weeks |
| 28 | Chronological: 26 weeks · Adjusted: 14 weeks |
| 32 | Chronological: 26 weeks · Adjusted: 18 weeks |
| 34 | Chronological: 26 weeks · Adjusted: 20 weeks |
| 36 | Chronological: 26 weeks · Adjusted: 22 weeks |
Baby born July 1, 2025. Calculated as of January 1, 2026. Other inputs kept at the calculator's default values. Results calculated by this calculator.
Why use an Adjusted (Corrected) Age Calculator?
Track a premature baby's development against the right milestones.
Important factors that can affect your results
- Usually used until about age 2.
- Exact gestational age at birth.
- Your pediatrician's guidance.
Frequently asked questions
When do doctors stop using adjusted age?
Typically around age 2, though this can vary — always follow your pediatrician's guidance.
Does this apply to full-term babies?
No — adjusted age is only relevant for babies born before 37 weeks gestation.
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Last reviewed November 2026 · How we build and check our tools · Report a problem