PPI is Imaginary! PPI vs DPI vs Resolution

Does changing the PPI really increase or decrease the image quality? How is DPI different from PPI? What actually is Resolution? In this lesson, we will answer all these questions, understand the difference between PPI, DPI, and Resolution, and delve deeper into what they actually mean with the help of fun examples, experiments, and a little bit of math. I hope you enjoy this video. Thank you so much for watching :)

► TIMESTAMPS:
00:00 Why PPI Doesn't Make Sense?
03:19 What is Pixel?
04:09 Cameras and Resolution
05:52 What is the Length of a Pixel?
07:02 Is PPI Imaginary?
08:14 When PPI Makes Complete Sense
12:15 What is DPI?
12:58 Why Experiments are Important
13:36 Further Reading

► ARTICLE: "PPI vs. DPI: what’s the difference?" by Colette Pomerleau:

► Recommended Software & Gear:

► PiXimperfect Merch Store:

► PiXimperfect Actions:

► Let's Connect:

[eddiemin]

Reminds of a vendor I dealt with once for a digital ad. Their designer called me to tell me that I needed to resubmit the art because it needed to be 300x600 at 300dpi. It was indeed 300x600 but I couldn’t get why dpi mattered. So I asked if they’re planning on printing it because that’s too small for print regardless and he said “no, it’s for online only”. I figured it’s pointless trying to explain so I just went into photoshop and changed the dpi from 72 to 300 and sent it back. My younger self would have wasted the next 20+ minutes arguing my point but I had enough experience by that point to know better lol.

[BHFilms]

Summary: If you arent going to print anything, dont worry about PPI. And DPI has nothing to do with anything digital, only the printers capability.

Great video my guy!

[samworth]

jesus christ! FINALLY - someone that actually explains it well. all those other tutorials - i kept saying "that doesn't even make sense." they forget to emphasize the physical-digital aspect of all of this.

[evanmavros]

The visuals along with the context is outstanding. Your educational abilities are off the charts. You are a fery rare human being Unmesh!

[rainmakr]

8:20 is the key part of this video. PPI is a physical measurement and is (should be) used in hardware specs. Monitor spec sheets used to indicate the PPI. Maybe they still do. Most of the time these days you only hear monitors referred to as a 2k, 4K or 8K display (or whatever) and you are left to do the math on your own.

Back in the day, PPI *did* matter in web design as some browsers would display images based on the PPI/DPI and not based on the length & width specified in the code which sometimes threw off the page layout.. For VGA (or was it SVGA?) monitors, 72 DPI/PPI was the norm. It would also cause issues when printing a raw image file (right-click & print). Then the printer would print at whatever PPI or DPI was specified.

The only time PPI matters in Photoshop is when exporting and specifying length & width in a physical measurement (ie. inches). That's when PPI might need to be specified. Anymore, though, it's standard practice to export the full, high-resolution document and let the output device or publishing software (be it to print or screen) do the conversion.

[Z-Diode]

Some theoretical lessons now and then are always welcome to complement your outstanding practical lessons. 🤓

[mikeswazey-du]

wow I got to say, after watching HOURS of YouTube tutorials. Your are by far the best in terms of getting straight to the point and giving us viewers what we want. this actually taught me something within the first minute, THANK YOU!!

[ON]

*I think this is an important lesson for photoshop, I once had to get a flex board printed for one of my business, I sent the image to the agency in high ppi but not very huge size in inches, the agency person asked for higher size again and again, in the end as the image in high dpi and full inches had the size of 1 GB or something I simply decreased the ppi and increased the size in inches, was thankful it was okay...*

[HNTAutumnleaf]

How is he so good in explaining stuff? My teachers always seem to make it look, like the most unreachable thing to achieve. But here he is, the calm and explaining perfectly.

[Refractd]

Thank you for explaining this. I feel like I've been explaining this to people for 20 years when they talk about PPI incoherently. I feel like at some point this was explained to people incorrectly, and it was never 'corrected' for them. Asking for a 300 dpi image when i send them a 72 dpi image.. because they wanted a higher resolution - but the funny part is, they weren't printing it. they were asking for the wrong thing! they just wanted more pixels in the end.

[the-pixel-whisperer]

I have been blessed with a TON of teachers on YouTube. Unmesh, you are the best of them all.

[austinross]

This brought me back to school so quickly! We had a similar debate in class on ppi and resolution. It gave me a better understanding of using a seemingly irrelevant data metric as a tool in my belt to use when determining photo quality when needing to print the final result. Your content is great Unmesh and thank you for reviving my interest in this field! Also, your videos got me to finally budge and buy a graphics tablet... I couldn’t be happier :)

[marvelchuruk]

Its always astonishing how subjects that I struggled with to understand for a time, are CRYSTAL clear in the first minute of your video....you have a gift to teach!! Thank you!

[almost_harmless]

Perfectly explained.

As far as I can tell, the confusion often (not always) stems from what printers ask of a customer (who is not into graphics) for e.g. an A4 with a 300 dpi image, who then asks their web designer or digital artist (who often, not always, have no clue about printing) who then argues that the resolution they have used is good enough, citing pixels. The client get confused by the words and demands and that confusion and frustration then seeps back into the mind of both those that print and digital only artists, who both then think everyone else is a moron. I was a client before I was a digital artist, and then I worked in printing. I have seen it all...

[jcjackman]

I started following you 4 days ago and I can't believe the amount of information I've been learning from you....Love From The Philippines ❤️❤️❤️

[Crlarl]

I get your general point but I take issue with one aspect: There is always a physical property to resolution. Unless you plug your brain into your computer directly, you have to convert pixels into linear dimensions. Whether you're viewing the image on a phone, monitor, projector, paper, anything at all, it now has spatial dimensions. Likewise, taking an image also has spatial dimensions with a scanner or camera. Inside a computer, these numbers are arbitrary but when they get rendered to the user, it becomes fixed. Maybe it's more helpful to think of pixels as "dimensionless units" much like degrees or radians.

[AmaSharapova]

OMG. This is the best video I have seen in my life. I never understood the ppi and gave up on it))) But you have changed it all for me! Thank you! Amazing job.

[EricAtRandom]

The PPI is used in printing. The idea is if you draw a 1-inch square in Photoshop, it prints 1 inch wide on paper when not scaled. The moment you scale an image to fit a page during printing, PPI becomes irrelevant once again.

But if you were printing a template for drilling screw holes to mount a power strip on the wall, for example, you want the scale to be precise. One inch on the screen must equal one inch in the print.

[criptoejesus]

I also just thought of another great use case as too why DPI actually does and can matter even more.

VR Gaming, the more pixels you can cram together in a small screen the better the overall resolution and clarity will be especially when you take into consideration the scaling and tricking your eye into believing that something that is technically super tiny is projected to be this massive 200" TV and fake all of reality around you!

[keithcurtis]

Thank you. I have to explain this to folks about once a month. Most of my background is in digital pre-press and getting across the idea that there is no such thing as an "inch" in digital graphics can be maddening.