Understanding the measurements of inches to pixels is important to know when dealing with images. An inch is a common unit of measurement both on and offline. But when you’re resizing images on the web, you’ll need to know how to convert inches to pixels.
You want to understand what's JPEG and PNG, you will understand details between this two things.
Converting inches to pixels properly is important when resizing. If you do it right, your image will come out with the highest possible quality.
Table of contents:
To convert inches into pixels, you need to multiply inches by resolution. Your resolution is measured by DPI. Your DPI will be multiplied by the dimensions in inches.
For a quick reference and example, check out this chart:
Resizing an object with an ideal conversion will not lead to noticeable changes in quality. However, certain changes will lead to predictably bad results, if done improperly.
When an image is enlarged, the image’s editor must create and add new pixel information. This will normally result in one of two changes.
First, the object may become highly pixelated, making an image very difficult to see. The larger pixels that are created will reduce the visible detail of the image substantially. Second, the image may become blurry, which is less unattractive, but still far from ideal.
Downsizing an image is much easier than enlarging one. If you need to downsize an image while maintaining professional quality, make sure you capture it in the highest resolution possible.
The term “dots per inch” (DPI) is interchangeable with “Pixels per inch”. These two terms are interchangeable and refer to the resolution of an image. Your image’s DPI is the exact number of printed dots that would appear within one inch of an image when it’s printed.
Remember, a higher resolution doesn’t necessarily mean a larger size. Larger images often naturally have a higher resolution because higher resolution images are typically larger.
Finding your image’s DPI is easy. The method you use will depend on your computer’s OS.
DPI and PPI are often used almost interchangeably. But there are a few differences that separate the two.
Your image’s PPI is the number of pixels in one inch of an image viewed on a computer screen. In general, a higher PPI means a better resolution. Conversely, lower PPIs imply a lower resolution and therefore lower quality.
An image’s PPI contributes to its quality. If a digital image has too few pixels, the picture will carry less detail and appear pixelated. Digital images with more pixels simply have better detail. The amount of PPI is determined by the image size of the photo.
Keep in mind that some professional print services will request images that have a certain DPI before they can be printed. But what they normally mean is PPI, not DPI, so it can be a bit confusing.
At a glance, you can refer to a few indicators of quality.
larger files (relative to the image dimensions) will normally hold a higher-quality image.
The file size of an image can change according to where the image was posted. The way you transport the image also affects its size. For example, a photo on your smartphone might be around 2MB. But if you post that image and then it’s downloaded from Facebook, it will end up around 100KB. However, if you took that image and saved it on a USB, it would retain the same 2MB size.
Dimensions alone don’t tell much of a story. However, when compared alongside image resolution or file size, they do.
When it comes to image resolution, there are two separate scenarios. When you have an image on your computer, the PPI is important. When you print, DPI is the number you want to look at.
Not All Projects Need 300 PPI — When Lower Resolutions Are Fine
The 300 PPI guideline is standard for high-quality print, but it’s not a one-size-fits-all rule. Here’s when you can safely go lower, and when you can’t:
Use Case | Recommended PPI | Why It’s Acceptable / Risk | Notes |
|---|---|---|---|
Large posters / billboards viewed from afar | 100–150 PPI | Viewers are far enough away that fine detail is less noticeable | Larger buffers help (e.g. 150 PPI for closer-viewed posters) |
Web display (monitor / mobile) | 72 PPI to 150 PPI | Screen PPI varies; more important is pixel dimensions, not “PPI” label | Always test on actual devices |
Newspaper printing | 150–200 PPI | Newsprint quality is lower — 300 PPI is often overkill | Check with your printer’s spec sheet |
Archival or fine art prints | 300 PPI or higher | You want maximum fidelity and sharpness | Especially important for small details, text overlays |
Bear in mind: downscaling (reducing dimensions) generally preserves visual fidelity better than upscaling. If your original is massive, you can export a properly scaled version and retain the original master file for future use.
If you want, you can change the DPI of an image. That’s because your DPI is just a measurement of print resolution. It has no impact on the size of a digital image. Even the file size is unchanged by the DPI.
f you’re editing an image you plan to print, setting your target DPI before resizing is a good idea. This will keep the resolution after printing in line with your expectations. It will also keep your image from becoming too small to print at the size you want to print with.
An appropriate DPI is more important when you’re planning to use a printer. The “standard” DPI for an image set for the printer is 300. In some cases, it can be as low as 150, but going lower will have a noticeable impact on its quality.
If you don’t need to print an image, you have less to worry about. The main challenge is maintaining quality when enlarging an image.
Under normal circumstances, a higher PPI will mean a better resolution. Conversely, a lower PPI will mean a worse resolution.
Enlarging an image that looks as good as the original size is difficult. But you don’t need to worry…
Design Wizard has a free conversion tool for resizing images. While you’re resizing your image, you can also experiment with the other design tools. If you also want to change the image’s brightness, contrast, or transparency, you can do so at the same time. Try to kill a few birds with one stone!
Large images, particularly ones with a high resolution, will be slower to load. If you’re displaying your image on a website, you don’t need to have a super-high DPI.
Your average 15-inch laptop will be able to capably display images of up to 100 DPI. But the image’s DPI doesn't have to be much higher to appear amazing. For a long time, a DPI of 72 was considered ideal for images displayed online.
If you’re downloading an image, the file’s size is the only worthwhile indicator of download time.
Key practices include using the appropriate file format (such as JPEG for photos and PNG for graphics with transparency). Pikwizard PNG images are a great option for high-quality, transparent graphics, especially when you need crisp visuals across different devices.
Consider an e-commerce store uploading product photos intended for catalog print and web display. If they upload images scaled only by inches (e.g. 8 in × 10 in) but don’t convert to the appropriate pixel dimensions for their print resolution or screen usage, they risk fuzzy prints or oversized files that slow page loading.
For example:
A 5 in × 7 in image at 300 PPI yields 1500 × 2100 px. If they mistakenly upload at just 5 × 7 px per inch (i.e. 5×7 px) or at a low PPI, the printed result will be pixelated.
On the flip side, scaling an image to ultra-high pixel dimensions (e.g. 6000 × 9000 px) when not needed inflates file size, harming page speed especially on mobile.
The ROI: by correctly converting inches to pixels, designers and web managers avoid rework, protect image quality across media, and keep web performance optimal.
Go ahead and try the Design Wizard conversion tool. It’s free.
You can resize your image the easy way and ensure it retains its quality. If you need to resize an image for a specific purpose, there are fast ways to do that. Design Wizard has all the standard sizes of social media banners. You can resize:
Whether or not you want to use the Design Wizard templates, there are other features you can use. You can crop your images and add layers to them. You can edit grid, blur, and saturation. There are different filters you can play with and you can change the tint. You can also edit the contrast and transparency of your image.
If you need to resize and edit an image, why not kill two birds with one stone. Make all these changes and more on Design Wizard.
Multiply the number of inches by the target resolution in PPI (pixels per inch).
pixels = inches × PPI
For example: for 8 in at 300 PPI → 8 × 300 = 2400 px.
PPI determines how many pixels are used per inch when printing. A higher PPI means more pixels packed in, yielding better print detail (up to a point). It also influences the pixel dimensions you need to meet a physical size requirement.
Not directly. When designing for screen, what matters most is pixel dimensions, not the labelled “PPI.” Many screens’ physical PPI differ, so what really counts is how many pixels your image is wide × tall.
PPI (Pixels Per Inch) refers to the digital image resolution (how many pixels in an inch of your photo).
DPI (Dots Per Inch) is a printing metric — how many ink dots a printer places per inch.
In practice for conversion, we usually use “PPI” because we’re converting digital image requirements (inches → pixels).
Yes, in some contexts. For large prints viewed from a distance, or for web use, you can often drop to 150 PPI or even lower while keeping visual quality acceptable. Always test and balance quality vs file size. (See passage above for guidance.)
Start with a high-resolution original or master file.
Don’t upscale beyond your source’s resolution (you’ll get blurring or pixelation).
Use proper export settings (compression, color profiles).
For print, also consider bleed and trim margins when determining final pixel dimensions.
Yes. If you change the physical inch size, you must recalc:
New pixels = (new inches) × (chosen PPI).
Always ensure the result matches or is less than your original image’s pixel dimensions to avoid quality loss.