I Drafted My Own Pants!

We have passed 200 days in quarantine. I've finished sewing up my party dresses. I've made a full workout wardrobe. I've sewn loungewear for both me and my husband. I needed a PROJECT. So of course I turned to my old standby, sewing jeans. Sewing jeans has never gotten old in the 8 years I've been doing it mostly because they are never perfect. I always find myself wanting to tweak one thing or another after making them. And as someone with not much pattern-drafting knowledge, it was a bit of a shot in the dark every time I made a new slash or pivot in my pattern. 

However, this time I decided it would be different. After making a few pairs in the past month, I decided to try drafting the pattern myself. It seemed like just the type of big project to keep me busy for a couple of weeks. And the results have been so, so worth it. 

Pattern: self-drafted ;)
Fabric: 1.5 yds stretch denim
Cost: $20

What started me down this path was a post by Heather from Handmade PhD. If you're not familiar with her blog, Heather is a neuroscientist who started sewing bow ties for her husband and became obsessed with sewing. She is no-nonsense, prides function over frivolity, and usually makes very detailed pattern adjustments to just about everything she sews. It's fascinating!

Recently, she published a blog post about measuring herself for some new pants and I was very intrigued. Her basic method, which you can read about in great detail, involves measuring a grainline up the center of your ankle and knee, and then taking measurements on either side all the way up your leg to determine your body measurements for your new pattern. 

Now, she does this with a ruler but I am a very visual person. I put on some old black leggings and, with chalk, drew that grainline right on my pants. Here's my process if you'd like to follow along. 

Measuring for Pants

According to Heather, the grainline should be drawn perpendicular to the floor/pants hem and go straight through the center of your ankle and your knee. This should prevent the pant legs from twisting when worn. So that's where I started, drawing the line at the center of my ankle and knee up my leg. From there, however, your hips may not be distributed along the center of the grainline - they may swing outward (as mine do) or have more width inward (perhaps for a fuller belly and slimmer hips). So I kept drawing the line from my ankle and knee straight up, perpendicular to the floor. I also made sure that the inseam and outer leg seam of my leggings were positioned at the correct place on my body and marked them with chalk as well. 

Heather doesn't detail this part as much in her post, but I found that next it was helpful to draw horizontal marks on my body at key points. I marked my ankle, calf, knee, thigh, crotch, full hip, belly, and waistline with horizontal marks on my pants. I then measured the distance of each mark from the waistline and drew this grid on my paper. 

From there, at each mark I measured the distance from my side seam to the grainline and then from the grainline to the inseam, recording both measurements. So the ankle, calf, and knee should have the same width at each side of the grainline. Then going up you can see how my hips start to stick out, with higher measurements to the outside of the pants from the grainline than the inside of the pants. On my torso, I just took my measurements to the center of the pants, not all the way across, as this is how I'll cut my pattern piece. 

Repeating this for the back, on yourself, gets a bit tricky. I enlisted my husband's help drawing the grainline and then took my own measurements from there, using a mirror to make sure the tape measure was level. (Yes, this sort of request makes him think I'm very weird.)  

Here's what the measurements look like all written down. You can see the grainline running up the leg, then the horizontal marks at key places, and the measurement from the side to the grainline to the inseam for both front and back. 

Measuring and drawing the crotch is probably the trickiest part. You can read more about how Heather did this and she also relied on a blog post from Michele for specifics on measuring the crotch curve. I used Michelle's method to measure my crotch depth and height with an L-shaped ruler, and also double-checked this with a bendable ruler that I've used for pants fitting in the past. The crotch curve took further refinement over two muslins to get just right, but this gets you pretty far. In the image below, you can see I measured my crotch depth, height, and length for both the front and back. 

Drafting my Pattern

Did you ever take an art class where you copy a painting by drawing a grid over it and then reproducing the piece, square by square, on your canvas? Well, this is kind of like that. Once I had recorded all my measurements on my paper, I set about re-creating those on my pattern paper. I started by drawing a straight grainline down the center of the paper. I then drew perpendicular lines for my waist, measured down the given amount, drew another for my belly, and so on for the full hip, crotch, thigh, knee, calf, and ankle. Once I had those markings, I measured out from the grainline and marked the distance for the inseam and outer leg. So at the waist, I marked 6.5" out from the grainline toward the side seam and 1.5" inches toward the center front, based on my measurements.

After I marked all my measurements it was time to connect the dots. This part was more art than science for me. Sometimes one marking seemed shifted and I had to shift it back in line with the others. I'm sure if my measurements had been perfect this wouldn't have happened as much, but I'm a living human marking measurements on myself using chalk lines drawn on my body, so it was bound to get a bit messy. 

Once I had drawn the front and back, I also trued my seams to one another making sure the front inseam was the same length as the back inseam and so on. This allowed me to fix things up even more and even created a few head-scratchers. The biggest problem was how to add enough crotch length and depth in the back without making the inseam too long (more on this later). I also puzzled with my curves, where my hips swing out then back in sharply to meet my knees. In my muslin, drastic curves didn't lay quite right on my body. In this instance, I found it was best to smooth the curves as much as possible. Because this pattern was for stretch jeans, I also found I could cheat the measurements slightly where needed, making them slightly more snug than measured to avoid drastic curves.

Adding Ease and Seam Allowances

What I now had on paper was a pattern for my body with no seam allowances or wearing ease. To determine how much ease you want to add, it can be helpful to reference your favorite pattern and compare the body measurements to the pattern measurements listed on the envelope. For example, Heather recommended half to one inch of ease at the waistband and added 1 inch of ease around her hips and 2 1/2 around her calves for looser her hiking pants.

For mine, I knew I wanted close-fitting pants sewn up in fabric with at least 25% stretch. Based on my muslin, I actually subtracted four inches from around my hips and thighs (an inch at each the front and back side seams). This is called negative ease and will rely on the stretch of the pants to fit me. I tapered this up to zero ease at the knees and calves based on how the muslin was fitting me. 

Once I figured out my desired ease, I added my seam allowances. I did a standard 5/8" all the way around EXCEPT for the side seams. For the side seams I like to use a 1" seam allowance. This gives me a bit of wiggle room in case my fabric isn't as stretchy as I'd like or is more tightly woven. I highly recommend this as it's rare to have two pairs of pants ever fit me exactly the same. 

Making a Muslin(s)

After all this drafting, I was so excited to start on my muslin. Would it fit me perfectly? Was this a disaster and I should just stick to purchased patterns? My first fabric unfortunately wasn't as stretchy as I thought, but the pants still fit surprisingly well given the custom measurements. Success!

Of course, they also gave me a good sense of what needed adjusting. First, I actually ended up repeating the above measuring and drafting process one more time, as I had gotten better at taking my measurements. After that, the main thing that needed adjusting, as I mentioned earlier, was the crotch curve. I had made my measurements as close as possible to the body and the crotch was a bit too contoured: it needed some wearing ease and smoothing out or else it was going to give me a huge wedgie! I lowered it slightly and smoothed out the curve where the front met the back. I also deepened it slightly and removed some of the height from the top of the pants so everything would sit where it should. 

My second muslin is fully wearable and what I'm wearing in this post. I also made a third pair out of a thick stretch knit that's similar in weight to a ponte, which  you can see in this post as well. For the second pair, I baste fit it to start and made a few small tweaks here and there - smoothing out the top waistline, the leg curves, etc. But in all these were fairly minor tweaks and I am pretty happy with the final fit. There's room for my butt, room for my thighs, the knees hit where they're supposed to, they're not too tight and not too loose. Definitely the best-fitting skinny jeans I've ever made. The one thing I changed between the second and third version was to move the inseam slightly toward the back. I'd heard jeans were supposed to have an inseam that was slightly forward, but I had done it by too much. 

That said, looking at these pictures I can see that I might want to take a wedge out of the front as I'm seeing some wrinkles there at the crotch. Interestingly enough is they are lot less prominent in the ponte version. I'm not sure if that's a difference in the fabric or maybe has to do with the zipper insertion, so I'll have to play around with that. That and I will lower the waistband a smidge, as it really is quite high as is. Jeans fitting is never done!

Comparing My Self-Drafted Pattern to Commercial Patterns

After drafting my pattern, I was very curious to know how it compared to other similar patterns I've sewn in the past (note: I haven't actually sewn the Cashmerette Ames or the Megan Nielsen Ash, but have heard good things so wanted to see how they'd work on me, hypothetically). 

Over the years, I've learned that an L-shaped curve works best for me and this was borne out by my new block. The image below shows how my back crotch curve, one of my biggest trouble spots, compares to these patterns. The Thread Theory Lazo Trousers, Cashmerette Ames, Colette Clover, and Closet Core Ginger Jeans best match this shape and, of those I've sewn, have worked well for me. The Style Arc Misty, Megan Nielsen Ash, and Deer & Doe Safran are all much too shallow or J-shaped for me and would need to be deepened. Pro tip: If you know your general crotch curve shape and are curious whether a pants pattern is going to work for you, you can usually look up the sewalong or user photos and find a photo of the actual pattern piece. Very helpful! That's what I did here for the Ames and Ash patterns that I didn't already have on file. 


Beyond the crotch curve, there are usually a few other adjustments I need to make to my pants. I shared recently that I realized I should be making a full thigh adjustment as my thigh measurement is often much bigger than patterns are drafted, even when they fit me at the hip. I also sometimes need a knock knee adjustment to shape the pattern from my full thigh curving inward toward my knees. For this adjustment, the torso of the pants on front and back is pivoted out toward the hip. 

Looking at the rough comparisons below, I can see that I would probably need to do a knock knee adjustment on the Style Arc Misty, the Megan Nielsen Ash, and the Deer & Doe Safran (clearly these patterns are not working for me, even though I love my Safrans!). I especially remember this from sewing up a few different patterns from Style Arc - they all had drag lines at the outer thigh, a tell-tale sign of needing a knock-knee adjustment. 

Even for the patterns with an L-shaped crotch curve and legs at the right angle, you can see in the image above that the crotch curve STILL needs to be deepened/widened to fit me. I have a 5 inch deep back crotch curve and there doesn't seem to be a pattern out there that fits that, especially for close-fitting pants. 

Looking at these images, I realized that, in the past, I had been deepening the crotch curve all wrong. Typically, I would extend the crotch curve to get the space I needed. You can see this method on the left in the image below. While this gave me the needed 5" of depth, it made the inseam too long, giving me folds of fabric at the inseam under the butt. By looking at my new block, I realized that what I should have been doing to adjust most patterns was to shift the whole back torso out toward the side seam, which widens the curve without changing the inseam. Once the top portion is shifted out, you blend the hip line into the leg line. For me, this also gives me the room in the thighs that I need. 

Going back to drafting the pattern from scratch, this is why it was so important (and helpful) to take my measurements from the middle line going up the back of my leg. It helped me understand that I needed to add most of the width for my butt from the middle of the pants going out toward the hip rather than in toward the crotch. 

But why make all these comparisons? For one, it's interesting to benchmark my shape to the standard pattern blocks from other popular patterns. It helps me understand where I'm "standard" and where I need a custom fit. For example, wide-legged pants usually fit me fine right out of the envelope because they avoid some of my major trouble spots - they are not close-fitting at the crotch, thighs, or knees. 

This is not to say that these pattern companies did a bad job or that I'm better than them at pattern drafting. When you buy a pattern, you are not only paying for the fit but also the way the pattern pieces fit together, the instructions, and the style lines of the garment. And I certainly don't expect every pattern to fit everyone right out of the envelope, especially something as tricky as skinny jeans. Making up my own pattern has been so instructive in how I might need to adjust professional patterns in the future. 

As for my jeans, I am super excited about them and have plans for many more (once I re-stock on denim). It's funny because I mentioned in an earlier post that I actually don't have much occasion to wear real pants right now, but when you have a pair that fits this well you know I'll be busting them out for every social-distance hangout. 


  1. Very well done. I will pass this on to friends who are struggling with pants fitting. If I feel ambitious, I may also draft my own block. Thanks also for the links.

  2. what a great analysis, it's so interesting to see all the comparisons. I find the Ash jeans to be a good fit for me but I think some of it relies on stretch denim. Recently I tried a couple of pants patterns from Patrones and they fit with zero adjustments so I might have found my ideal pants patterns. looking forward to seeing how you develop this pattern.

  3. So much work, and so worth it. You look wonderful in your new pants! Although it confirms my love for dresses and my aversion to pants. :)

  4. This is great information! I think I have similar crotch depth issues and I’ve just never truly been able to crack the code. I never would have thought to slash/shift at the hip! I’ll remember that if I ever get back to making fitted pants again.

  5. This is fascinating! This seems like a lot of work but so worth it. I have yet to find a non-stretch or non-culottes pants pattern that works for me truly, and the fit adjustments I research don't seem to work. I wish this was a service someone provided, since all I really want to do is choose the fabric and sew, haha. Great job!

  6. useful, i want to try by myself
    great post!thank you for your share!
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