Here we are again with another client who brought us a DVD full of photos "in the highest resolution" - each one 50 MB. And in the end it turns out this is supposed to be an A5 flyer viewed from a meter's distance. Meanwhile, his competitor ordered the same print run with 2 MB images and the visual effect is identical. The difference? The first client paid more for file transfer and extended his production by half a day.
The "300 DPI for everything" myth is one of the most expensive legends in the printing industry. Not because it's completely false - but because it's imprecise. The truth is: the required resolution depends on the type of print, printing technique, viewing distance and - most importantly - on how many details are actually visible to the naked eye.
What does DPI actually mean in printing context
DPI - Dots Per Inch - is how many dots a printing machine can place on one inch. But attention: this is not the same as image resolution, which is given in PPI (Pixels Per Inch). When you say a photo has "300 DPI", you're actually talking about its resolution in pixels per inch.
An offset press prints at 2540 DPI resolution - much higher than your 300-pixel photo. But each pixel of the image will be "broken down" into several printer dots, because the machine must reproduce different levels of gray and colors using halftone screens - a grid of dots of varying sizes.
Practical example: A 3000×2000 pixel photo printed at 10×7 cm = 300 PPI. The same photo printed at 20×14 cm = 150 PPI. Quality remains identical, only the pixel density per centimeter changes.
Screen ruling - where the magic happens
The key to understanding resolution is screen ruling, measured in LPI (Lines Per Inch). This is the number of screen lines per inch - the higher the ruling, the finer the dots and smoother the tonal transitions.
Newspaper uses 85 LPI - you can clearly see the dots, but it's cheap and fast. A color magazine uses 150 LPI - smooth transitions, beautiful photos. An art catalog might have 200 LPI - details like in a gallery. Each ruling requires a different minimum image resolution.
The rule is: image resolution should be 1.5–2 times higher than print ruling. For typical offset printing (150 LPI) this means 225–300 PPI. Hence the famous "300 DPI" - but this is just a starting point, not a dogma.
How much you really need - specific values
Time for numbers you can immediately apply in practice. These values come from 15 years of experience and thousands of print runs - not theoretical calculations.
Business cards and small formats (up to A6)
300 PPI - absolute minimum, but 400 PPI is better. A business card is a product you view from 20–30 cm distance, so every defect is visible. Logo on a business card should be vector, but company photos - already in high resolution.
We've seen business cards with logos "extracted" from PowerPoint files at 72 DPI. The result? Pixelated logo at the first business contact. Better to pay 100 dollars more for file preparation than lose a client due to poor print quality.
Flyers, folders, brochures (A5–A3)
250–300 PPI is the sweet spot. An A5 flyer viewed from 40–50 cm distance doesn't need astronomical resolution. A 2000×3000 pixel photo is easily enough for a full A4 page.
A mistake we often see: client sends 8000-pixel photos "to make it the best". The file weighs 200 MB, transfer takes an hour, and the visual effect is identical to a 20 MB file. In offset printing you're not printing on photographic paper - paper structure and printing ink have their physical limitations.
Don't overdo the resolution: A photo above 450 PPI in offset printing is a waste of space and time. The printing press cannot reproduce more details - excess pixels simply get "lost" in the screening process.
Posters and large formats (A2 and larger)
150–200 PPI is enough, and sometimes even 100 PPI is fine. You view an A1 poster from 2–3 meters distance - detail that you'd see on a business card up close doesn't matter here.
The calculation is simple: the larger the format and the greater the viewing distance, the lower resolution you can use. A 6×3 meter billboard can easily be printed with 50–72 PPI images - you view it from 50 meters distance from a car going 60 km/h.
Text and vector elements
Text should always be vector - no discussion. Font saved as image, even at 1200 DPI, will be worse than the same text saved as vector curves. It's physics - vector has no pixels, so it can be printed at the full resolution of the printing press.
Logo, icons, illustrations - everything with sharp edges should be vector. Saving a logo as PNG "to have transparent background" is a mistake you'll pay for with worse print quality.
Paper type matters
On newsprint (60–70 g/m²) ink soaks in and spreads - even a 600 PPI photo will look like 150 PPI. On glossy coated paper (150–300 g/m²) every detail is visible - here high resolution really makes sense.
Uncoated offset paper (80–120 g/m²) is a compromise - good color reproduction, but without excessive sharpness. 250–300 PPI photos will look great, higher resolutions don't provide noticeable improvement.
Most important rule: adjust resolution to paper, not to your camera's capabilities. A 50 MB photo for a flyer printed on offset paper is like using a Ferrari to drive across a field - you can, but why?
Digital vs offset printing - different requirements
Digital printing (HP Indigo, Xerox iGen) has 812–1200 DPI resolution, but works differently than offset. No halftone screens, just direct toner application. Result: can reproduce more details from the same file.
In digital printing, a 200 PPI photo often looks better than the same 200 PPI photo in offset. But attention - this doesn't mean you need higher resolution. It means you can use lower and still achieve good results.
Most common mistakes that cost time and money
"Interpolation will save low resolution"
It won't. Enlarging a 150 PPI photo to 300 PPI in Photoshop is adding pixels that weren't there. The computer can guess what colors to place between existing pixels, but cannot recreate details that aren't in the original.
A 1000×1000 pixel photo enlarged to 2000×2000 weighs four times more, but isn't four times sharper. It's just more blurry and bigger. Better to use the original at lower resolution than artificial enlargements.
"The higher the resolution, the better"
Beyond a certain threshold - no. A 600 PPI photo in offset printing won't look better than 300 PPI, but will weigh four times more and slow down the press RIP. In extreme cases it can even cause print errors by exceeding memory limits.
"I saved from Word as PDF, so it's ready to print"
Word compresses images by default to 220 PPI and uses JPEG compression even if they were originally PNG. PDF from Word is not a file prepared for professional printing - it's a file prepared for home printing on an inkjet printer.
Word and PowerPoint destroy quality: These programs are not designed for preparing professional print files. They automatically compress images, change color profiles and add compression where it shouldn't be.
How to prepare images with appropriate resolution
First calculate how many PPI you actually need. Formula: image width in pixels ÷ print width in inches = resolution in PPI. Example: 3000 pixels wide photo for 10 cm (4 inch) print = 3000÷4 = 750 PPI. That's definitely too much - you can reduce to 1200 pixels and get 300 PPI.
In Photoshop: Image → Image Size, uncheck "Resample" and set desired resolution. If the program shows the file will be too small for planned print - then you can enable resampling, but better look for a photo in higher resolution.
Saving: for photos use JPEG with minimal compression (85–95% quality) or TIFF without compression. Leave PNG for graphics with transparent background. Always in Adobe RGB or sRGB color profile - the printer will convert to CMYK in their workflow.
Checklist before sending file
- Check actual resolution (pixels ÷ print size in inches)
- Make sure text is vector, not raster
- Logo and icons saved as vector (AI, EPS) or minimum 400 PPI
- Photos: 250-300 PPI for small formats, 150-200 PPI for posters
- CMYK format or leave RGB (printer will convert)
- Color profiles embedded in file
When it's worth paying more for higher resolution
There are situations where high PPI really makes sense - regardless of file cost and processing time. Art catalogs, photo albums, medical materials where detail can be crucial for interpretation.
Also premium products - business cards with UV varnish, invitations on pearl paper, book covers. Here print quality is part of brand communication, so it's worth investing in maximum resolution that printing technology can utilize.
But for typical marketing materials - flyers, folders, posters - reasonable resolution is a better choice than maximum resolution. You'll save time, money and nerves, and the visual effect will be identical.
DPI resolution 300 DPI PPI screen ruling LPI Photoshop CMYK Adobe RGB
Finally, the most important advice: if you're not sure what resolution to use, ask the printer before starting work. Every print shop has its standards, every machine has its capabilities. Better one phone call at the beginning than corrections at the end, when the job is already on press.
Have questions about preparing files for print? Our technologists will help you choose optimal parameters for your project - you'll save time and avoid costly mistakes.