A custom poster needs a price that follows its size and a photo the customer frames themselves. Appify Custom Product Options does both on one Shopify product.
The customer picks a size, uploads a photo and drags a crop window over it in Image Edit mode. The edited image goes into the cart and arrives with the order.
What does a custom poster product need?
Four jobs, each handled by a different part of the calculator.
| Job | What the customer does | What you set up |
|---|---|---|
| Price by size | Picks or types a size | Size option and a pricing formula |
| Frame the photo | Drags a crop window over the upload | File upload plus Image Edit |
| Catch weak photos | Sees a warning in the editor | Resolution warning settings |
| Print the order | Clicks Done | Export settings and the Design Files link |
How do customers crop their own photo?
Image Edit is the part of the Product Designer built for uploaded photos. It opens a full-screen editor with the customer's photo loaded. They crop it and finish with Done in the top-right corner.
Set it up
- Add a File upload option. Label it something like "Upload Your Photo". You can set the accepted file types and the maximum file size.
- Add a Product Designer option. Set Linked file upload option to the upload you just made. With that link, the button opens Image Edit instead of the full designer.
- Open Designer (Step 5) and switch to Image Edit. Turn on the tools your buyers need.
- Open the gear icon. Set Image framing, the Done label and the export resolution.
Customers can also click Edit beside their uploaded file, so the button is optional.
Choose Drag selection for posters
Under Image framing, Drag selection keeps the photo fixed and lets the customer move a crop window over it. It is the setting made for photo prints.
The other choice, Drag image, does the opposite: the photo pans inside a fixed frame. Either way, the customer decides what ends up inside the poster.
Optionally turn on Fit artboard to image on upload. It sizes the artboard to the upload once, right after the photo arrives.
The customer chooses the framing. The edited image is the file that arrives with the order, so nobody on your team crops anything by hand.
Switch on the tools you want
Each tool has to be enabled in Step 5 before customers see it.
| Tool | What the customer gets |
|---|---|
| Crop | Aspect presets and orientation |
| Finetune | Sliders for brightness, contrast, blur and color |
| Filter | Preset looks on the photo |
| Frames | Borders, drop shadows and shape masks |
| Draw and Text | Notes, arrows or a caption on the photo |
On a phone, the editor switches to a layout built around the canvas, with the tools in a bar along the bottom. Customers pinch to zoom.
Want to see how it feels before you build it? The photo editor calculator breakdown shows a finished calculator with its settings.
Is Image Edit the same as the Product Designer?
Image Edit is one of the Product Designer's two modes. It is a focused editor for the customer's own photo.
Designer mode is the design-from-scratch canvas, with clipart, layers and an artboard whose size follows the calculator. It suits products where the design is the product, such as stickers or wallpaper.
For a plain photo poster, use Image Edit.
If you also sell posters with a headline or a name added, put a second button on the same calculator. One opens Image Edit for the photo, and one opens Designer mode for the text and graphics. The guide to letting customers design their own products covers that second button.
Text only, priced by the letter? How to sell personalized mugs and engraved gifts shows per-character pricing with a live text preview.
How do you price a poster by size?
Add a Dimensions option for width and height. Then price from the area.
You create the area as a pricing variable, width times height, and name it AREA. A rate per square foot or square meter times that area is a one-line formula. Add a paper or finish choice with its own rate and the formula reads that too.
The price updates on the product page as the customer chooses size and paper. The full pricing build, with material rates and quantity breaks, is in how to price custom signs by size, material and quantity. A poster follows the same steps.
How do you stop low-resolution photos before they print?
Turn on Warn customers about low image resolution. The editor compares the pixels in the upload with the size of the print area and warns the customer while they work.
Two settings matter here.
- Recommended resolution (DPI). The level the warning checks against.
- Export DPI. The resolution of the saved print file. The default is 300.
A poster shop can export at 300 and warn at 150. That way customers swap out weak phone photos before ordering.
With a recommended resolution of 300, customers see a gentle caution between 150 and 299 and a stronger warning below 150. Set it to 150 and they only hear about photos under that line.
Here is the arithmetic for a 24 by 36 inch poster. It is a worked example, not a store figure.
- At 300 DPI: 24 x 300 by 36 x 300 is 7,200 by 10,800 pixels.
- At 150 DPI: 24 x 150 by 36 x 150 is 3,600 by 5,400 pixels.
- A photo 3,000 pixels on its long side: stretched across 36 inches, it works out to about 83 DPI. That is under the 150 line, so the customer sees the warning.
The settings above come from the print quality and production output options in the designer.
What arrives with the order?
When the customer clicks Done, the save runs on its own. A proof PNG is always made.
A print-ready PNG with bleed is made when you turn it on in the export settings. The edited file replaces the original upload.
Each order line shows a visible Design Files link. It opens a page with the proof image and download buttons for the files, so your team or your printer starts from the right file. Which formats a printer expects is covered in what file formats print vendors need from custom orders.
Want the customer to confirm the crop first? Turn on Enable design review workflow on the Buttons tab for Image Edit. It adds a review step before the final save.
Do you need a calculator for every poster?
No. Assign one calculator to a collection, such as your Posters collection, in the Placement & Styling tab. Every poster in that collection uses it, including posters you add next month.
Manual and automated collections both work. A new product that matches an automated collection gets the calculator without another publish.
What if the customer wants a different size after adding to cart?
They can change it from the cart. A customer who added a 24 by 36 poster and realizes they need 18 by 24 taps Edit options, changes the dimensions and updates. The quantity and their other selections stay filled in.
Turn it on under Optional Features with Allow edit from cart. It is on by default for new calculators. The cart editing setup is in the help docs, and the post on letting customers edit configured products in the cart.
Check it before you go live
- Upload a sharp photo and a weak one. Confirm the warning shows for the weak one and stays quiet for the sharp one.
- Crop the photo on a phone. Drag the selection, tap Done and check the result.
- Price three sizes by hand. Compare each with the live price on the product page.
- Place a test order. Open the Design Files link and download the print file.
- Change the size from the cart. Look for Edit options and run it once.
FAQ
Can customers crop their own photo on Shopify?
Yes, with Appify Custom Product Options. Image Edit mode lets them upload a photo and drag a crop window over it before adding to cart.
Who decides how the photo is framed?
The customer does. They move the selection themselves, and the edited image is the one saved with the order.
Can one product sell every poster size?
Yes. Size options drive the price, so one calculator covers every size, and you can assign it to a whole collection.
Will low-resolution photos be caught?
Yes, if you turn on the resolution warning. Customers see it in the editor while they work, before they add to cart.
Can a customer change the poster size after adding it to the cart?
Yes. Edit options on the cart line reopens their choices with everything filled in, so they change the size and update.
Let them frame it. You get the print file.
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