Use the Department of State’s free photo tool to:
Start Photo Tool
– select a digital image stored on your computer
– resize and rotate it if necessary
– crop it to a square image of exactly 600 x 600 pixels, and
– save it to your computer to submit online or for printing
Please note: This tool is intended for photo cropping only. A Department of State employee will make the final decision whether your visa photo is acceptable or not for your application.
Notes
Photos of too large, too small and correct head photos in the Help section are missing
Source
https://travel.state.gov/content/travel/en/us-visas/visa-information-resources/photos/digital-image-requirements.html (via Wayback Machine)
Photo Tool screenshots
