Photo Size Guides
Plain-language guides to photo file sizes, KB limits, passport photo dimensions, signatures and image formats, so your upload is accepted the first time.
- Basics · 3 min readHow to Compress a Photo to an Exact KB SizeA step-by-step guide to getting any photo under a KB limit such as 20 KB, 50 KB or 100 KB, on a phone or computer, without making it blurrier than it needs to be.
- Basics · 3 min readKB vs KiB: Why a "20 KB" Photo Can Still Be RejectedKilobytes can mean 1000 or 1024 bytes depending on who is counting. Here is how the difference causes upload errors, and how to pick a file size that passes every check.
- Troubleshooting · 3 min readWhy Online Forms Reject Your Photo: 9 Causes and FixesFile too large, wrong format, wrong dimensions or a HEIC photo from an iPhone: the most common reasons an upload form refuses a photo, and how to fix each one.
- Photo ID · 3 min readPassport Photo Size in Pixels: mm, Inches and DPI ExplainedHow to turn a passport photo size in millimetres or inches into pixels, with worked examples for 35 × 45 mm, 2 × 2 inch and 50 × 70 mm photos.
- Signature · 2 min readHow to Scan and Resize Your Signature for Online FormsCapture a clean signature with your phone camera, then resize it to the box and KB limit an application form asks for, such as 400 × 160 pixels under 20 KB.
- Formats · 2 min readJPG vs PNG vs WebP: Which Format to Use for UploadsWhat the difference between JPG, PNG and WebP actually is, which one gives the smallest file for photos, and which one forms are most likely to accept.
- Basics · 2 min readDPI vs Pixels: What Actually Changes a Photo's File SizeWhy changing a photo's DPI does not make it smaller, what pixels and DPI really mean, and what to do when a form asks for a photo at 200 or 300 DPI.
- Formats · 2 min readHow to Upload iPhone HEIC Photos to Forms That Want JPGWhy iPhone photos are saved as HEIC, why upload forms reject them, and four ways to get a JPG instead, including a setting that makes the camera save JPG.
- Photo ID · 2 min readPhoto and Signature Size for Exam and Job Application FormsA practical checklist for preparing the photo and signature that exam, recruitment and admission portals ask for, with the typical size ranges and how to meet them.