Image File Size & Resolution

What file size do I need to print well?

A plain-English guide to the resolution, file size and colour space we recommend for fine art giclée printing — with a quick reference table of common print sizes.

The Short Answer

How much resolution your file really needs.

Getting the image file right is the single biggest factor in print quality. For fine art giclée, here's the specification we work to — and what it means in practice.

150 PPI Minimum

The absolute floor

At 150 pixels per inch at final print size you'll get an acceptable fine art print. Below this, soft edges and visible pixellation start to show on close inspection.

300 PPI Ideal

The gold standard

At 300 ppi at final print size, your print will hold crisp detail at any viewing distance. This is where fine brush strokes, fabric weave and hair detail really sing.

Both figures are measured at 1:1 — that is, at 100% of the final print size, not at the file's native dimensions.

What PPI Actually Means

Pixels per inch, at printed size

PPI is simply how many pixels of image detail fit into one inch of your final print. A 3000 × 2400 pixel file printed at 10 × 8 inches is 300 ppi. Print that same file at 20 × 16 inches and it drops to 150 ppi — the pixels have to stretch further to cover the larger area.

The target ppi is always measured at the size you want to print. Your camera doesn't know what size you're going to print at — it's up to you to check.

Colour Space

RGB, with an embedded profile

Please save your files in RGB colour space with an embedded ICC profile — either sRGB for everyday work, or Adobe RGB (1998) if your original scan or photo captured a wider gamut.

Untagged files and CMYK files will be converted on our end, but you'll get a more predictable result if the file arrives with its colour profile intact.

One Important Warning

Don't enlarge a small file in Photoshop.

If your file is under 150 ppi at your target print size, the temptation is to resample it upwards in Photoshop to hit the number. Please don't. All that does is invent pixels that weren't there in the first place — the file ends up larger but no sharper, and sometimes worse.

If your file genuinely needs to be printed larger than its native resolution allows, send it to us as-is. We have professional upsampling software that handles the maths properly, preserves edge detail, and gives a substantially better result than a manual Photoshop resize.

Quick Reference

Minimum pixel sizes for common print dimensions.

A handy reference if you're sizing files for a specific print — minimum at 150 ppi, ideal at 300 ppi.

Print size
Min (150 ppi)
Ideal (300 ppi)
6 × 4″ postcard
900 × 600 px
1800 × 1200 px
8 × 10″
1200 × 1500 px
2400 × 3000 px
A4 (210 × 297mm)
1240 × 1750 px
2480 × 3508 px
A3 (297 × 420mm)
1750 × 2480 px
3508 × 4960 px
16 × 20″
2400 × 3000 px
4800 × 6000 px
A2 (420 × 594mm)
2480 × 3508 px
4960 × 7016 px
24 × 36″
3600 × 5400 px
7200 × 10800 px

Figures assume a viewing distance typical of gallery or home display. For prints that will be scrutinised up close, aim for 300 ppi.

Not sure about your file?

Send it to us for a free file check — we'll tell you honestly whether it will print well at the size and paper you have in mind, and suggest any tweaks before you commit to an order.