Print-prep for T-shirt designers and POD shops
4500×5400 PNGs at 300 DPI for Amazon Merch, Printify, Printful, and Redbubble — with transparency preserved, batch processing, and the right size per platform.
Challenges we solve
Common problems that slow down your workflow — and how Ratio Ready handles each one.
Every POD platform wants a different file size
Amazon Merch wants 4500×5400 PNG. Printify wants 4500×5400 for tees but 4000×5000 for hoodies. Redbubble wants 7632×6480 for art prints. Manually resizing the same design for every platform burns design time on busywork.
Lose transparency = lose the whole sale
T-shirt designs need transparent PNG backgrounds — JPG fills with white, making the design unwearable on coloured shirts. One missed export and the file gets rejected by Merch's automated pipeline.
AI-generated designs ship at the wrong size
Midjourney and DALL·E default to 1024×1024. Amazon Merch wants 4500×5400. Without AI upscaling that preserves transparency, your AI-art portfolio gets bottlenecked by manual upscale work.
Scaling a winner across the catalog is slow
When a design hits, you want it on T-shirts, hoodies, mugs, totes, phone cases, stickers — every product type. Doing 10+ resizes per winning design, one platform at a time, slows down the moment you're trying to capitalise on momentum.
T-shirt design print-prep, bundled
Upload one design, get every POD platform's required size in one ZIP — transparency preserved, 300 DPI stamped, ready to upload.
- Amazon Merch: 4500×5400 PNG with transparency
- Printify: 4500×5400 (tees) + 4000×5000 (hoodies) + custom
- Printful: 1800×1800 to 4500×5400 per product type
- Redbubble: 7632×6480 for art prints, 4500×5400 for apparel
- Society6: 6750×9000 for art prints, custom per product
- Alpha-aware AI upscaling for AI-generated 1024px sources
- Batch processing — up to 50 designs per upload
- Preset presets for fast multi-platform output
- API access for automation via Make.com / n8n
- 300 DPI metadata stamped on every output
Your workflow with Ratio Ready
Upload your T-shirt design
Drop your transparent PNG (or batch of designs). Procreate, Photoshop, Affinity, AI-generated — all work. Each gets validated for transparency and resolution.
Pick target platforms
Select which POD platforms you're uploading to (Merch, Printify, Printful, Redbubble, Society6). Ratio Ready outputs the correct size for each in one job.
Process across platforms
Each platform's required size is generated from the master file. AI upscaling kicks in automatically if the source is below target. Transparency preserved through every step.
Download per-platform ZIP
Get a ZIP organised by platform — merch/, printify/, printful/, redbubble/. Upload each folder's PNG to its respective platform without any further processing.
When you’d use this
Four common scenarios where Ratio Ready saves the most time:
- Scaling a winning T-shirt design across the Merch catalog. Your design is selling on a T-shirt. Putting it on hoodies, tanks, mugs, phone cases, totes, and stickers means 6+ different sizes. Ratio Ready outputs every Merch product spec from one upload — replaces 4+ hours of one-at-a-time Photoshop export.
- Sourcing AI-generated designs and shipping at Merch resolution. Midjourney generates at 1024×1024 — too small for Merch's 4500×5400 minimum. Auto AI upscale brings the source to 4500×5400 with transparency preserved (alpha-aware), so your AI-art portfolio scales without manual upscale work between platforms.
- Multi-platform launch of a new design. A new design ships to all 5 POD platforms simultaneously. Ratio Ready outputs Merch (4500×5400), Printify (4500×5400), Printful (per-product), Redbubble (7632×6480 art / 4500×5400 apparel), Society6 (6750×9000) in one ZIP. Upload to each platform from the matching folder.
- Refreshing an old design portfolio for higher-tier products. Your 2-year-old designs were sized for T-shirts only. To add canvas prints (Society6 art prints need 7632×6480) you need bigger source files. Batch-upscale via Ratio Ready, then list across all art-print POD platforms with one workflow.
Common mistakes
Mistakes I’ve seen (and made) that cost real time and refunds:
1. Saving designs as JPG (transparency lost)
T-shirt designs need transparent PNG. JPG fills transparent areas with white — unusable on coloured shirts. Always start with PNG, stay PNG through the pipeline. Ratio Ready preserves alpha channel from input to output, including through AI upscaling.
2. Using a 12 MP source for Merch's 4500×5400 spec
12 MP sources (4000×3000) fall short of Merch's 4500×5400 requirement. The upload either fails or ships soft. Run AI upscaling first — Ratio Ready detects the gap and runs the upscale automatically when you target Merch dimensions.
3. Mixing CMYK and RGB color modes
POD platforms expect RGB. CMYK files often appear washed out, fail validation, or print with shifted colors. Always work in RGB. Ratio Ready outputs RGB by default; if you receive a CMYK source, convert in Photoshop before uploading.
4. Forgetting the safe zone on apparel placement
T-shirt print areas have safe zones — content too close to the edge gets cut off in printing. Keep critical content (logos, text) within the inner 80% of the print area. Decorative elements can extend to bleed.
5. Skipping the platform-specific spec check
Each POD platform has slightly different requirements. Don't assume Merch's 4500×5400 works everywhere — Redbubble's art prints want 7632×6480, Society6 wants 6750×9000. Always check the platform's current spec page before bulk uploading.
Frequently asked questions
Ship to every POD platform from one upload
Merch + Printify + Printful + Redbubble + Society6 in one ZIP. 50 free Creative Credits on signup.