Kaiya Baby Size Guide
Kaiya Baby Size Guide
Not sure which size to choose? Start with your baby's current height and weight, then check the product style. A good fit should feel secure without being tight, with enough room for natural movement.
Use this guide for Kaiya Baby swaddles, basic sleep sacks, Sleep Suit Sack 3-in-1, and bundles.
How to choose the right size?
Choose by height and weight first, not age alone. Babies grow at different speeds, so the age label is only a starting point.
If your baby is between two sizes, use the fit around the neck, chest, and length as the final check. The sleepwear should not pull tightly across the chest, and the neck opening should never be loose enough for your baby's head to slip through.
If a size feels too small, move up. If a size feels too roomy around the neck or arm openings, wait before using it for sleep.
Swaddle Size Chart
Kaiya Baby swaddles are designed for newborns and young babies who still need a snug, secure wrap. Choose the size that matches your baby's current height and weight.
| Size | Height | Weight |
|---|---|---|
| 0-3 Months | 21-25" / 53-64 cm | 7-13 lb / 3-6 kg |
| 3-6 Months | 22-27" / 56-69 cm | 14-18 lb / 6.5-8 kg |
| 0-6 Months | 21-27" / 53-69 cm | 7-18 lb / 3-8 kg |
Fit note: If your baby's head can pass through the neck opening, do not use that swaddle for sleep.
Basic Sleep Sacks Size Chart
Use this chart for Kaiya Baby basic sleep sacks, including sleeveless and long sleeve sleep sack styles. These are designed to give babies wearable warmth while leaving room for natural leg movement.
| Size | Height | Weight |
|---|---|---|
| 0-6 Months | 21-27" / 53-69 cm | 7-18 lb / 3-8 kg |
| 6-18 Months | 26-33" / 66-84 cm | 16-27 lb / 7-12 kg |
| 18-24 Months | 32-39" / 81-99 cm | 25-36 lb / 11-16 kg |
Fit note: The sleep sack should sit comfortably at the shoulders and chest, with room for the hips and legs to move. Do not size up so much that the neck or arm openings become loose.
Sleep Suit Sack 3-in-1 Size Chart
The Sleep Suit Sack 3-in-1 is made for older babies and toddlers who need more leg freedom for rolling, crawling, standing, or moving around before and after sleep.
| Size | Height | Weight |
|---|---|---|
| 6-18M | 26-33" / 66-84 cm | 16-27 lb / 7-12 kg |
| 18M-3T | 32-39" / 81-99 cm | 25-36 lb / 11-16 kg |
| 3-4T | 37-47" / 94-120 cm | 32-46 lb / 15-21 kg |
Fit note: Choose this style when your baby or toddler needs more leg separation than a traditional sleep sack. The fit should allow movement without dragging, twisting, or pulling at the shoulders.
Bundle Size Chart
Kaiya Baby bundles may include different sleepwear pieces, so check the size range before adding a bundle to your cart. If the bundle includes more than one product type, make sure each piece matches your baby's current height and weight.
| Size | Height | Weight |
|---|---|---|
| 0-3 Months | 21-23" / 53-58 cm | 9-12 lb / 4-5 kg |
| 3-6 Months | 23-27" / 58-69 cm | 14-18 lb / 6.5-8 kg |
Fit note: If your baby is close to the upper end of a bundle size, check the individual product style before choosing. A baby may fit one piece well but be ready to size up in another.
Quick fit checklist
- The neck opening should sit close without slipping over the baby's chin or face.
- The chest should feel comfortable, not compressed.
- There should be room for the hips and legs to move naturally.
- The length should allow movement without extra fabric bunching heavily at the feet.
- Stop using any sleepwear if the zipper sticks, breaks, or catches.
- Keep all Kaiya Baby sleepwear away from open flames and direct heat. Natural fabrics are not flame resistant.
Still between sizes?
If your baby is between sizes, choose the size that gives the safest neckline and the most comfortable body fit today. Do not size up only to make the product last longer.
If you are choosing between two styles, think about how your baby sleeps now:
- Choose a swaddle if your newborn still needs a snug wrap and has not started showing signs of rolling.
- Choose a basic sleep sack if your baby needs wearable warmth with a simple enclosed bag shape.
- Choose a Sleep Suit Sack 3-in-1 if your baby or toddler needs separated-leg movement.
- Choose a bundle if the included pieces match your baby's current size range.
If you are still unsure, contact us before ordering, and we will help you choose the best fit.