Quick answer
Choose the 0–4 month size for most newborns and use the adjustable knot to fine-tune the fit; move to the 5–18 month size once the hat leaves deep marks or the knot no longer sits comfortably. The stretchy fabric gives you room to adjust, but it should feel snug, not tight.
Why the adjustable knot changes sizing
A top knot hat is not a fixed-size cap. The knot at the top lets you loosen or tighten the hat around the head, so the same hat can fit a range of head sizes within its size band. That is why the 0–4 month size can work from the first week through the early months, and why you do not need a perfect measurement to get a secure fit.
The trade-off is that the knot must be tied firmly enough to stay put. A loose knot lets the hat slide up or off, especially on a newborn with little hair to grip. Check the knot after dressing and again after a feed or nap.
What to expect from the stretch
The fabric is designed to be ultra-soft and breathable with a hint of stretch. That stretch helps the hat go on easily and accommodates normal head growth, but it is not a substitute for the correct size. If the fabric looks overstretched or the hat keeps creeping up, the size is too small.
Stretch also affects how the hat feels against the skin. A hat that is stretched tight can leave temporary marks on the forehead. A hat that is too loose will not stay on during sleep or travel.
When a newborn hat feels too tight or too loose
A hat that is too tight leaves red marks that do not fade within a few minutes of removal, or it pulls at the ears. A hat that is too loose slides down over the eyes or comes off when baby turns their head. Both are fit signals, not fabric defects.
If you are between sizes, start with the smaller size and loosen the knot. The 0–4 month size is intended for newborns, while the 5–18 month size is cut for older babies. Do not size up early just to get more wear time; an oversized hat is more likely to slip.
Top knot hat fit questions, answered
How do I know if the hat fits my newborn?
Put the hat on and tie the knot so the brim sits just above the eyebrows. You should be able to slide one finger under the edge without stretching the fabric tight. If the hat leaves red marks that last more than a few minutes, loosen the knot or size up. Check for marks after 10 minutes of wear.
Should I size up for a newborn to get more wear?
No. Start with the 0–4 month size for a newborn. The adjustable knot gives you room to grow, and an oversized hat is more likely to slip over the eyes or come off. Move to the 5–18 month size when the smaller size leaves marks even with the knot loosened. Use the knot first; size up only when the smaller size is clearly outgrown.
How tight should the top knot be?
Tie the knot firmly enough that the hat does not slide when baby turns their head, but loose enough that the fabric does not pucker around the brim. Retie after dressing and after feeds, since the hat can shift. A secure knot is firm, not tight.
Can my baby sleep in a top knot hat?
A well-fitted hat can be worn for warmth, but check that it stays in place and does not slide over the face. If the hat moves during sleep, it is too loose. Remove the hat if it bunches or covers the eyes. Recheck the fit before sleep.
How much stretch is normal?
The fabric should stretch enough to go on easily and return to its shape. If the hat looks thin or overstretched across the head, it is too small. If it feels baggy and will not stay put even with the knot tightened, it is too large. Stretch should help the fit, not replace the right size.
Product facts
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Top Knot Hat - Ferra: Available in 0–4 months and 5–18 months, with an adjustable knot for the perfect fit from newborn to 4 months. The knot lets you tighten or loosen the same hat as your baby grows, so you can get a secure fit without buying multiple sizes in the first months.
Top Knot Hat - Ferra
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Top Knot Hat - Della: Made with ultra-soft, breathable fabric with just the right hint of stretch. The stretch makes the hat easier to put on and helps it stay comfortable, but you still need to check that it is not stretched tight enough to leave marks.
Top Knot Hat - Della
