Bootstrap Fashion and Sewly both give you a pattern drafted to your measurements, but the design comes from different places. Bootstrap Fashion sells a catalog of fixed designs that it drafts to the measurements you enter, one pattern per purchase. Sewly drafts a pattern from a photo or a description you provide and lets you change its options. If the design you want is in the catalog, Bootstrap Fashion is a straightforward choice; if you are starting from an image, Sewly is.

How does Bootstrap Fashion work?

Bootstrap Fashion runs an online shop of custom-fit sewing patterns. At the time of writing (October 2026), you choose a design, enter your body measurements following its measuring instructions (or pick a standard size), pay for the pattern and receive the files by email, usually within half an hour. Files are offered for home printers (A4, Letter and other sizes), for large-format printing and for plotters, in PDF, PLT or DXF. Bootstrap Fashion is particularly known for its made-to-measure DIY dress form patterns, which let you sew a dress form shaped like your own body. It also sells through an Etsy shop.

The catalog runs to hundreds of designs. Because each design is fixed, what you customize is the fit, not the style.

How does Sewly work?

Sewly starts from what you want to sew: a photo, a screenshot, a link to a public Pinterest pin, Instagram post or shop page, or a description. The AI identifies the garment and its details and picks the closest garment type in Sewly's library with matching options. A drafting engine then draws the pieces from flat-pattern blocks with your measurements and the right ease.

You can change the design afterwards: lengthen the skirt, swap the sleeves, change the neckline or the fit, and the pattern redraws at once. A 3D mannequin built from your measurements shows the silhouette, in a plain color or in the print from your photo (a preview, not a fabric simulation). On a paid plan you print at true scale on A4, US Letter, A3, Tabloid, A0, 36 × 48 in or for a projector, with the sewing guide as a PDF.

When is Bootstrap Fashion the better choice?

  • The design you want is in its catalog. You get that exact design, drafted to your measurements, with no need to describe it.
  • You need a dress form. A made-to-measure dress form is a Bootstrap Fashion specialty and not something Sewly makes.
  • The garment is outside Sewly's library. Sewly does not yet draft tailored jackets with collars and lapels, coats, jeans with a fly front, shirts with collar stands, lingerie or swimwear.
  • You prefer to pay per pattern. If you sew a few garments a year, buying the ones you need can cost less than a subscription.
  • You use a plotter or CAD software. PLT and DXF files are available; Sewly exports PDFs and a projector file only.

When is Sewly the better choice?

  • You are copying a look. Starting from the picture saves you hunting through a catalog for something close.
  • You want to adjust the design. Options such as length, neckline, sleeves and fullness are part of the pattern, and you can try them before printing.
  • You want to see it first. The 3D preview on your measurements helps you judge proportions, for example where a hem falls on you. Read more in why see your garment in 3D before you cut.
  • You want a guide for your version. Sewly's guide covers the steps for your options, the pieces with cut counts, notions such as zip and elastic lengths, cutting layouts and fabric quantities for 110, 140 and 150 cm (45, 55 and 60 in) wide fabric, and you can ask it questions while you sew.
  • You sew often. The Maker plan, at $7.99 a month or $59 a year, includes 30 new AI patterns a month and printing for every pattern you make.

What do they share, and what are the limits?

Both depend on your measurements. Take them carefully with a tape measure, ideally with help; our measuring guide explains each one. Both are drafted by software rather than fitted on your body by a person, so a toile remains the safest step for fitted garments.

Bootstrap Fashion's limit is that the style is fixed: if your dream dress is not in the catalog, you adapt the closest design yourself. Sewly's limit is its library: 20 garment types at launch, each with many options, and printing requires a paid plan.

Can you use both?

Yes. A made-to-measure dress form is a useful companion to any made-to-measure pattern, including Sewly's: you can check a toile on it when there is no one around to help with fitting. You might also buy catalog designs for the garments Sewly does not cover and use Sewly for the looks you find in photos.