Printful and Printify bulk prep: per-product specs done right

Printful and Printify both use per-product templates. A t-shirt has different specs than a mug. A mug has different specs than a phone case. There's no single magic size that works across their whole catalog.

The good news: ReadyPixl handles this with one preset per product type. Set up the spec once, save the preset, run on every batch of that product. Switch presets when you switch products.

This article walks the recipe + lists the most-common product specs.

Printful and Printify specs

Always check the platform's design template page for the exact product you're prepping — both platforms publish per-product templates with the precise pixel dimensions, and specs change occasionally.

Printful's general guidance:

• Standard t-shirt design area: 12″ × 16″ (3600 × 4800 px at 300 DPI). Some larger DTG products: 15″ × 18″ (4500 × 5400 px at 300 DPI).
• Resolution: 150–300 DPI (150 is enough; 300 is the max — going higher just bloats the file)
• Format: PNG for transparent backgrounds (DTG printing requires it), JPEG for images
• Color profile: sRGB

Printify uses a similar per-product template approach, with sizes that can vary depending on which print provider in their network you're using. Check the product page on Printify for the exact spec.

For both: open the product page on the platform → look for the "File guidelines" or "Design template" download. That's the only authoritative source.

(Source: Printful help center, "What is DPI, resolution and actual print file size?" + per-product file guideline pages.)

The pipeline

The pipeline is the same shape as the Amazon Merch pipeline — what changes is the canvas size in the Reposition step.

Step-by-step (using t-shirts as example)

1. Open the editor. Go to readypixl.com.

1. Drop your design folder in.

1. Add Color Removal. Default Tolerance handles most solid-background designs.

1. Add Trim. Defaults are fine.

1. Add Reposition. Settings (for standard t-shirts at Printful's 12″ × 16″ DTG print area):

• Unit: px
• Canvas Width: 3600
• Canvas Height: 4800
• DPI: 300
• H-Align: C · V-Align: C
• Padding: 50–100

(For Printful's larger 15″ × 18″ DTG products, use 4500 × 5400 instead. Check the specific product's File guidelines page for the exact spec.)

1. Click Download All. Output zip ready to upload.

1. Save as a preset. Critical for this workflow — name it "Printful t-shirts" or similar.

1. For each new product type, repeat steps 5-7 with that product's spec. Save each as its own preset:

• "Printful standard t-shirts" — 3600 × 4800 (12″ × 16″)
• "Printful large DTG t-shirts" — 4500 × 5400 (15″ × 18″)
• One preset per other product you sell, using each product's published file guideline
• etc.

Once your preset library exists, the workflow per batch is: load the right preset → drop designs → Download All. 30 seconds.

Tips for working across multiple product types

• Set up presets in advance for every product you sell. The first time setup takes 15-20 minutes total. Every batch after is one-click.
• Name presets clearly. "Printful t-shirts," "Printify mugs 11oz," etc. When you have 10+ presets, naming matters.
• For products with a wide canvas (like mugs), your designs need to be designed for that aspect ratio. A square design centered on a wrap mug template (2700 × 1110) leaves a lot of empty side space — usually that's fine, but plan for it.
• For asymmetric products (phone cases with notches), download Printful/Printify's actual design template (with notch cut-outs visible) and design within those bounds. ReadyPixl handles the bulk transformation; the design itself needs to fit the product.
• Watch file sizes. Big canvases × big batches = big zips. 200 t-shirts at 4500 × 5400 PNG ≈ 1-2 GB.

Differences between Printful and Printify

Both follow the same per-product template pattern, but:

• Printful tends to publish more detailed product templates (with bleed lines, safe zones marked).
• Printify publishes templates per product and per print provider — the same product (e.g., t-shirt) can have slightly different specs depending on which print provider in their network you're using.

For both, always check the actual product page on the platform before locking in your preset. Specs occasionally update.

Tips for the design itself (before ReadyPixl)

• Design at the target spec from the start — opening a 1000 × 1000 design and trying to upscale it to 4500 × 5400 doesn't work as well as designing at 4500 × 5400 originally.
• Use a print-friendly font. Some thin or extreme fonts don't print well. Stick with weights and styles that have body to them.
• Check colors against the print provider's color limits. Some print methods (DTG vs DTF vs sublimation) handle bright colors differently. Both platforms' product pages include this info.

What to do if a design comes out wrong

Same troubleshooting as Amazon Merch bulk prep. The pipeline is the same — only the canvas size changes per product.

What to read next

• The pipeline concept
• Reposition — for the canvas-sizing details
• Amazon Merch bulk prep — single-spec workflow
• Etsy design prep — for prepping product images (vs designs)