Pants Fitting: The Crotch Part 1


Part 1 – Record your measurements

One semester in my pattern making course, I had the opportunity to learn about drafting pants. One of them specifically, drafting a pant block from a skirt sloper. That process really made everything about fitting pants click. I made the connection between the major fitting points of the body to the pattern. I also remembered watching my instructor have a tissue fitting session of a pants pattern on a student and explaining what to look for. It was all so fascinating! I started to see exactly what I think most of us have been missing when it comes to pants fitting… understanding the crotch. So I started to implement what I have learned from school, along with my own experiences, I made a routine when it comes to measuring and checking a pattern.

This post I will only cover the crotch fitting. The whole entire fitting process of pants is some what extensive and I think the crotch area is where a lot of people have the most issues. So hopefully I can keep it short and to the point.


Record the following measurements

You will need to record the following measurements and compare the following measurements to the pattern in this order. It must be done in this order to get the most accurate fit. All the following measurements can be easily taken with a L shape square ruler and a measuring tape.

  1. Crotch hook or extension (For front and back)
  2. Crotch length (Length total and front/back separately)
  3. Crotch depth

One of the common responses I received from people was that they didn’t have an L shape square ruler. So in this tutorial I will show you how to make one so we can record the majority of the measurements needed.

Instagram highlights link on this topic.

Make your L shape ruler


  1. 1 sheet of cardstock, magazine board, or cardboard
  2. Pen, pencil, or marker. I prefer to use 3 different color markers.
  3. Ruler
  4. Tape

A quicker way to take your crotch length and have seperate measurements for the front and back. I reccomend taping two measuring tapes together at the beginning 


Record your crotch hook/extension and crotch depth on ruler.

  1. Wear fitted clothing when taking your measurements. I reccomend wearing leggings where the inseam falls directly in the middle of your leg.
  2. Place a thin elastic around your natural waist. This is where you have a natural bend in your side. Usually where you would like to have the top of a pair of high waisted pant to be. Have this elastic parallel to floor. 

3. Mark the back crotch hook. Place the L shape ruler in between your legs from the back like so… (see picture below). Make sure that the bottom of the ruler is touching your seat and parallel to floor. The other side of the L shaper ruler touching your buttock and perfectly perpendicular to the floor. It is important that the L shape ruler is not tilted in any way. 


4.Mark at the top of the bottom of the ruler in one color, where the inseam of the garment fall on the ruler. When marking stand as straight as you can, if you can’t have someone help you mark.


5.Repeat for the front, marking the front in another color. Things to note for the front is if your bust gets in the way of keeping the ruler from touching your belly and staying perpendicular to floor, cut the ruler shorter. 


6. While the L shaper ruler is placed in the front, go ahead and mark your crotch depth. This marking will be along the side of the ruler that is perpendicular to floor. Go ahead and mark where the elastic that was placed on your waist falls on the ruler. Your ruler should look like this… 

Blue line: my waistline

Green line: my front crotch hook/extension

Purple line: my back crotch hook/extension


7. Measure your crotch length using the measuring tape. Place the joining point of the two tapes in the middle of your seat (where the inseams intersect). Take note of the full length, front and back in seperate measurements. This will be from front waistline -down and up to the back waistline. 


Now you should have all the following measurements recorded and marked on the L shape ruler.

-Crotch hook/extension front

-Crotch hook/extension back

-Crotch total length

-Crotch front length

-Crotch back length

-Crotch depth

Next blog post will be Part 2: Comparing those measurements to pattern.



  1. Just wanted to pop in to say you are fabulous! I am a recent follower (and admirer) first on IG and now your blog. I am determined to make pants fit and this Information is invaluable. Thank you!


  2. Love this! Thanks so much for trying to help us ‘fitter-newbie’s’ . If the older method worked well, we’d all be using it! I’m invested in this newer method, and have great hopes. It looks very promising. Thanks so much for sharing your knowledge!


Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s