The Customei editor is fast — but like any canvas app, it has practical limits. Following these guidelines keeps the editor responsive, the storefront snappy, and your print files clean.Documentation Index
Fetch the complete documentation index at: https://docs.customei.com/llms.txt
Use this file to discover all available pages before exploring further.
Layer count
- Recommended: under 100 layers per template.
- Typical template: 10–30 layers.
- Above 150: you may notice the editor slow down on dragging and selection.
Canvas size
- Design at the final print resolution. Scaling up at publish time introduces blur.
- At 300 DPI, most products land between 1500 × 1500 and 4000 × 4000 px. Much larger than that and you’ll feel the editor slow down during zoom and pan.
- If your product needs a truly massive output (billboards, banners), split it into tiles and generate each tile as a separate template.
Image size
- Customer uploads: allow up to the cap set in the option set field (default is merchant-configurable, typically around 10 MB per file).
- Library images: no hard cap, but anything above 5000 px on the longest side is usually overkill. Customei downscales to the target print resolution at publish time.
- SVG: use for simple, sharp vectors (logos, icons). Avoid for complex illustrations — the storefront rasterizer is simpler than a full SVG engine.
Fonts
- Upload
.woff2when you can — it’s the smallest format and loads fastest on the storefront. .ttfand.otfare accepted but larger.- Keep your library’s active font count modest. Each font adds to the storefront bundle; 3–5 carefully chosen fonts are plenty for most brands.
Text layers
- Set a character limit on option-set text fields. Long customer inputs blow up the canvas and make the print unreadable.
- Curved text breaks down at extreme radii — test every curve on a mockup.
- Warped text is expensive to re-render on every keystroke. For fields that change often (e.g. customer name), prefer regular text + tint, not warped text.
Image quality vs bundle size
Every image you add to a template ships in the published bundle. To keep product pages fast:- Prefer shared library assets. Images reused across templates dedupe in the bundle.
- Compress before uploading. PNG-8 or WebP for clipart, JPG for photos.
- Transparent PNGs are fine — just don’t oversize them. A 4000 × 4000 PNG for a small icon is wasteful.
Storefront performance
- First paint on the storefront is faster when the bundle is smaller. Audit big templates: do you really need that 8 MB PSD-style PNG?
- Option fields that mutate many layers on every keystroke (e.g. a text field that drives three separate layers) are the most common cause of lag. Prefer fewer bindings per field when possible.
- Background removal on uploads adds 2–5 seconds per upload — test on slow connections.
Print-file gotchas
- Transparent areas in an image layer print white (or your product’s base color). Test on the mockup.
- Thin strokes (< 2 px at 300 DPI) may vanish on some print processes. Use a minimum 2 px stroke for any outline you want visible.
- Small text (< 6 pt at final size) is unreadable on most print media. Set a floor on your option-set text fields.
When in doubt
- Test on a real mockup before publishing.
- Place a test order before handing over to a customer.
- Download the print file from an order and open it in an image viewer; if it looks wrong there, it’ll look wrong on the product.