Muslin Fitting Session
Put on your muslin, work through the checklist, and log every change. The tool translates your muslin measurements to pattern adjustments and links to the right tools — so nothing gets lost between the fitting and the cutting table.
0 of 12 checked · 0 need adjustment · 0 changes logged
1. Center front grain
Look at the center front of the garment. Is the grainline perfectly vertical?
If the grain swings to one side, the pattern piece was cut off-grain or the fabric shifted during sewing.
2. Center back grain
Check the center back. Is the grain vertical?
Same as front — off-grain cutting causes the garment to twist.
3. Shoulder seam position
Look at the shoulder seam from the side. Does it sit at the top of the shoulder, or has it rolled forward or backward?
If you can see the seam from the front, it's rolled forward (forward shoulder adjustment needed). If from the back, it's rolled backward (rare).
4. Shoulder width
Does the shoulder seam end at your shoulder point (where the arm begins), or does it overhang or fall short?
Overhang = shoulders too wide (narrow them). Falls short = shoulders too narrow (widen them). Measure the difference.
5. Bust fit
Look at the front bodice across the bust. Is there pulling, gapping, or excess fabric?
Horizontal pulling = too tight (FBA needed). Vertical wrinkles at CF = excess length. Gapping at the armhole or neckline = too large (SBA). Darts should point at but not reach the bust apex.
6. Waist seam position
Tie a piece of elastic around your natural waist. Does the garment's waist seam align with it?
If the seam sits above the elastic: garment is too short (lengthen). Below: too long (shorten). Check front and back independently — they may differ.
7. Waist fit
Is the waist too tight, too loose, or just right?
Pulling at waist = too tight (let out). Can pinch more than 1" of fabric = too loose (take in). Measure the pinch — that's your adjustment amount.
8. Upper back shape
Look at the upper back between the shoulder blades and at the lower back waist.
Horizontal fold at upper back = high round back. Horizontal fold at lower back waist = swayback. Pulling across shoulder blades = full upper back.
9. Hip fit
Check the fit across the hips (fullest point, usually 7-9" below waist). Is there pulling or excess?
Pulling = too tight at hip. Excess fabric = too loose. If bust and hip are different sizes, you need grading.
10. Sleeve fit
Raise your arms, reach forward, cross them. Does the sleeve restrict movement? Is the cap smooth?
Can't raise arms = bicep too tight. Diagonal wrinkles from armhole = cap ease issue. Puckering at cap = too much ease. Pulling at underarm = not enough ease.
11. Overall length
Check the hemline. Is it level? Is the length what you want?
Hem rides up in front = front bodice too short (FBA can cause this). Hem rides up in back = back too short. Uneven hem = possible grading issue.
12. Neckline fit
Does the neckline sit where you want it? Is it gapping or pulling?
Gapping at front neckline = neckline too wide or too deep. Pulling at neckline = too tight. Standing away from the body = too high.
How to use this tool
Step 1: Fitting Checklist — Put your muslin on and work through each checkpoint top to bottom. Mark each one as "Pass" or "Needs adjustment." If it needs adjustment, add a note about what you see.
Step 2: Change Log — For each item that needs adjustment, measure the correction on the muslin and log it. The translator converts your muslin measurement to the pattern adjustment amount (accounting for seam vs. fold, divide by 2, etc.).
Step 3: Summary — Review all your changes, download a PDF to take to the cutting table, and click through to the individual tools to apply each adjustment.
The measurement translation
The most common muslin mistake is getting the math wrong between what you measure on the garment and what you change on the pattern. Key rules:
- Pinch at a seam: The pinch is both layers. Pattern adjustment = pinch ÷ 2 per edge.
- Pinch at a fold (CF/CB): The pinch is one layer. Pattern adjustment = full pinch amount.
- Lengthen/shorten: The amount is direct. No division needed.
- Moving a seam: Measure the shift distance. That's the adjustment amount.
The tool applies these rules automatically when you select the location and change type.
Multiple iterations
Sometimes one muslin isn't enough. Save your session and start a new one for the next iteration. Previous sessions are listed in the Summary tab so you can track your progress from first muslin to final fit.
Name your sessions clearly: "Muslin v1 — initial fit," "Muslin v2 — after FBA," "Muslin v3 — final check."