Where/How to measure for a hat?

This will be a strange question, but it has me baffled. When measuring for the circumference of a hat, do you measure straight around, or on a slope? Middle of forehead or lower forehead? I’ve knit and crochet several spring and summer hats for my dd and they’re either too small (if I go by my measurements) or too big (when I estimate by comparison to the one that came out too small). I’ve matched gauge each time, so I’m kind of stumped on what I’m doing wrong here.

I created a list from my searches on the internet.

I don’t have this but it exists if anyone wants it. it’s a hat size book.
http://www.knitting-and.com/book.html

You can find head Circumference charts here…http://yarnstandards.com/headsize.html

You can also look at other hat patterns that can tell you how high a hat has to be.

Here are preemie baby measurements…http://www.carewear.org/patterns/knit/knit.cfm?pid=_p10_basic_knit_hat.cfm

http://www.bevscountrycottage.com/size-chart.html
that site gives you all sizing (width and height) for baby’s through adults - hats

Most hat patterns which give sizes in measurements (for example, “to fit 20”) mean the largest part of your head, circumfrence-wise. So for a lot of people, that’s at the top of their ears. Fool around with a cloth tape measure and figure out where the largest part of your head is, around, and that should set you good to go.

True, you can ignore the ears; the hat will stretch to fit over them.

I have a related question, which probably has a very simple answer but I really cannot find it.

How do you measure the circumference of a knitted hat, especially while it is being knitted? One author I read suggested the use of a flexible tape measure, but it is not easy to hold a tape exactly around the circumference of the hat, and at the same time spread out the hat, even with a second pair of hands. When knitting from the top down, it would be very handy to be able to tell when to stop making the increases.

I had the idea that the easiest would be to measure the diameter of the hat, then multiply by the value of pi (3.14), which is supposed to give the circumference of a circle. However, I have not found this advice in any knitting handbooks, so is there a catch? Is it because the head is not a perfect circle or what?

The diameter times pi would be if the hat was open in a circle, but that’s tricky to get an accurate measurement. Flatten it out and measure across, then double the measurement.

Thanks, why did I not think of that?:hug:

See, this is the part that’s really frustrating for me, the advice of the so-called “experts”. Knit your hat until it covers the crown of your head. What exactly is the crown of your head? They never explain that? Is it the flat part of your head and you’re supposed to stop knitting when it covers the top of your head to where it begins to slope? If so, that’s way too big anyway. Then there’s the PI formula. Take your head measurement and divide it by three. That’s where you’re supposed to stop. Well, my head is 22 1/2 inches around. I go with the nearest multiple of 3 which is 21. A third of that is 7. I’m supposed to stop knitting after the hat is 7 inches in circumference or 3 1/2 inches from the hole start at the top. That’s WAY too big. It’s more practical for me to take this PI and subtract 1/2 an inch from that number. That’s about right. As for measuring circumference, I lay the hat flat. Measure across the hat and multiply that measurement by 2.

I’m still struggling with the hat sizing thing myself in both knit and crochet. Seems like one size is too small, another too big. The type of yarn you use makes a big difference with sizing. One of these days I’ll get it right and not have to work at it so hard.

Pi doesn’t really have anything to do with the head measurement for knitting because you measure the hat flat, not as a tube. The crown is the rounded part of your skull toward the back of the ears, which makes sense as you don’t wear the hat straight down but angled. They say to knit the length from your wrist crease to the tip of your middle finger, then start the decreases, but that’s about an inch too long. I usually just try it on and see where it hits me, beginning the decs when it’s about 2" from the ‘crown’.

On my first hat. For the Circumference, I measured around head, just above the ears. 59cm. Times that by 100% less negative ease (100%=15%=85%) 85%x 59cm=50.25cm) that’s the hat Circumference. Work out how many stitches using gauge swatch.
Gauge swatch: 5 stitches/cm
Cast on 50.15cmx5cm stitches. My hat fitted using this method.

2nd measurement: measure over top of head from bottom of one earlobe to the other earlobe and divide by 2. Mine was 18.5cm. This is how long, plus brim, to knit your hat, if knitting a watch cap. (Ie lies flat on top of head). So 18.5cm + 5cm brim = 23.5 cm total length of hat.

Crown measurement:
Method 1: put finger on forehead, draw straight, horizontal line to above your ear. Measure from this point to bottom of earlobe ( Mine 9.5cm) take this measurement from your earlobe to earlobe measurement. Eg 18.5cm=9.5cm=9cm crown

Crown Method 2: Place book on top of head. Place 2nd book on side of head. Measure the gap from top book to where side book touches side of head.

Crown Method 3: hat Circumference ÷(2xpi)= 50.15cm ÷ 6.28= 7.98cm.
Round up to 8cm, or not.
Use gauge swatch to work out number of crown rows/rounds.
Eg 4 stitches/cm
8cmx4stitches= 32 crown rows.