Version July 2025
| Tube size ID | Age/weight |
| 2.5 mm | 1000 to 1500 g |
| 3.0 mm | >1500 g to <8 months |
| 3.5 mm | 8 months to <2 years |
| 4.0 mm | 2 to <4 years |
| 4.5 mm | 4 to <6 years |
| 5.0 mm | 6 to <8 years |
| 5.5 mm | 8 to <10 years |
| 6.0 mm | 10 to <12 years |
| 6.5 mm | 12 to <14 years |
| 7.0 mm | 14 to <16 years |
This chart shows the sizes of low pressure, high volume, low profile endotracheal tubes that are appropriate for intubation in neonates, infants, and children. The ages shown for sizes ≥3.5 mm ID are those that are recommended by the manufacturer of the Microcuff brand.
After endotracheal intubation and confirmation of correct placement, appropriate sizing should be confirmed by assessing for leak at 20 cm H2O airway pressure. This table should be used in conjunction with UpToDate content on selection of endotracheal tubes for pediatric anesthesia.