The imgbox blog
Image guides & tutorials
Straight answers on image sizes, DPI, compression, file formats, and photo privacy — with the free tools to do each job right in your browser.
What DPI Do You Need for Printing?
The direct answer is 300 DPI for standard photo and document printing. Here's why, when 150 or 600 makes sense, and how to work out the real DPI your image will actually print at.
Passport Photo Size by Country (mm, cm, pixels)
The standard passport photo is 35x45mm (3.5x4.5cm) for most of the world, while the US and India-for-US use 2x2 inches. Here are the exact pixel sizes, head-height rules, and online file-size limits.
How to Compress an Image to a Specific KB Size
Portals like exam forms and passport applications reject photos over a fixed KB limit. Here is exactly how to hit 50KB, 100KB, or 200KB without guessing.
How to Reduce Photo File Size Without Quality Loss
Photos are huge because phone cameras capture far more detail than any screen or email needs. Here's how to shrink them dramatically while keeping them sharp.
Instagram Image Sizes 2026: Posts, Stories, Reels
Every Instagram image size that matters in 2026, with exact pixels, aspect ratios, and safe zones so your uploads never get cropped or blurred.
YouTube Banner Size & Safe Zone (2560x1440)
The full YouTube banner size for 2026 is 2560x1440, but only a 1235x338 center strip shows on every device. Here's how to design inside the safe zone.
HEIC vs JPG: Differences, Quality, When to Convert
HEIC saves space and holds Live Photos and depth data, but it won't open on many Windows PCs, Android phones, and older apps. This guide explains the trade-offs and how to convert when you need to.
PNG vs JPG vs WebP: Which Format Should You Use?
PNG, JPG, and WebP each win in different situations. This guide explains lossy vs lossless, transparency, file size, and exactly which format to pick for photos, graphics, and the web.
How to Remove GPS Location Data From Photos
Most phone photos silently embed the exact latitude and longitude where they were taken. Here's how to see that hidden data and remove it before you share.