A screen makes colour with light and a press makes it with ink, and light reaches colours ink cannot. This free tool reads your artwork in the browser, converts every pixel to CIELAB, and compares its saturation against the approximate limit of a generic coated-stock CMYK press — then shows you a simulated print alongside the original, and highlights every colour that will have to move. Turquoise, electric green and vivid blue are the usual casualties; yellows and warm neutrals survive almost untouched. It is a gamut approximation rather than a colour-managed soft proof, because a true proof needs your printer's ICC profile, and it runs entirely on your device.
Preview your colours
Drop your artwork here
One image — nothing is uploaded.
How to use it
- Add one image — Drag your artwork onto the drop area or click to choose it. The image is decoded onto a canvas in your own tab and the pixels are read there, so nothing is uploaded.
- Read the out-of-gamut figure — You get the share of pixels more saturated than a generic coated-stock CMYK press can reach, the pixel counts behind it, and a verdict — prints close to screen, some dulling expected, or visible dulling expected.
- Compare the two panes — The original sits beside a simulated print at the same size, because a percentage does not tell you whether the colours that moved were the ones the design depended on.
- Switch to "Show what shifts" — The second view paints every out-of-gamut pixel in a flat alarm colour, so you can see at a glance whether the problem is the whole sky or one flower.
- Decide whether to adjust the palette — If the flagged area is a background wash, desaturating it slightly in the file will look closer to the print than leaving it. If the piece depends on an electric turquoise or green, either accept the shift or rework the palette — no paper will reproduce it.
The problem this solves
The commonest complaint in print-on-demand is that the print looks flatter than the file did on screen. By the time it surfaces it is a refund, a reprint or a three-star review, and the seller has no way of knowing which part of the design caused it — so the same mistake ships in the next forty listings.
What it does
Side by side, not a number
The original and the simulated print sit next to each other at the same size, because a percentage does not tell you whether the colours that moved were the ones the design depended on.
Shows you where, not just how much
A second view paints every out-of-gamut pixel in a flat alarm colour, so you can see instantly whether the problem is the whole sky or one flower.
Hue-aware limits
The printable range is not one number — process yellow nearly matches sRGB while cyan-green is where ink gives up soonest. The check models that shape rather than applying a flat saturation threshold.
Honest about what it is not
This is an approximation of a generic coated CMYK gamut. It is not a soft proof, it does not know your supplier's press or paper, and the page says so rather than implying a precision it does not have.
Nothing leaves your browser
The image is decoded to a canvas in your tab. No upload, no account, no file stored anywhere.
Where it lives in PSDmate
Free and open on this page. Inside PSDmate the same thinking sits behind the pre-publish checks, which flag a file before a whole batch of listings goes out with it.
Questions
Why do my prints look duller than my screen?
Because a screen emits light and a print reflects it. Backlit pixels reach saturations that ink physically cannot, so the most vivid colours in a design get compressed to the nearest printable equivalent. The effect is strongest in turquoise, electric green and vivid blue, and barely noticeable in yellows, creams and earth tones.
Should I convert my files to CMYK before uploading?
Usually not. Most print-on-demand suppliers want sRGB and run their own conversion with a profile matched to their press, and converting early means converting twice. The useful thing is to know in advance which colours will move, and to adjust the artwork rather than the colour mode.
Is this the same as soft proofing in Photoshop?
No. Photoshop soft proofs against a specific ICC profile for a specific press and paper. This approximates a generic coated-stock CMYK gamut, with no profile involved. It is a good deal more accurate than guessing and a good deal less accurate than a real proof, which is why it is free and instant.
What do I do about the colours it flags?
Decide whether they carry the design. If the flagged area is a background wash, desaturating it slightly in the file will look closer to the print than leaving it. If the whole piece depends on an electric colour, either accept the shift or rework the palette — no supplier and no paper will reproduce it.
Does the file get uploaded?
No. The image is decoded onto a canvas in your browser and the pixels are read there. Nothing is sent anywhere and nothing is stored.
Read more
- Why Your Prints Look Duller Than Your Screen
- DPI, Resolution and Colour for Print-on-Demand
- PNG, JPG, WebP or TIFF for Etsy and Print
- T-shirt mockup generator
- Mug mockup generator
Other tools
- PSD Mockup Automation Without Photoshop — Every design across every template in one job, from the PSD files you already own.
- AI Art Generator for Print-on-Demand — Generate artwork at print resolution, with your own provider key and your own prompt library.
- Brand Kits, Frames and Layouts for Etsy Listings — Every listing image looks like it came from the same shop, without rebuilding it each time.
- Etsy Listing Video Maker — Turn the mockups you already rendered into the listing video Etsy pushes in search.
- Etsy Listing Automation and Bulk Upload — Render, write and publish a whole batch of listings to Etsy in one run.
- Etsy SEO and Listing Copy Generator — Titles, tags and descriptions written from the actual rendered image, not from a keyword you typed.