Open Safari browser on your iPhone
Visit convertheictojpg.org
Tap "Choose Files" button
Select photos from your Photo Library
Wait for automatic conversion
Tap "Download" to save JPG files
Files will be saved to your Downloads folder
You can select multiple photos at once
Make sure you have enough storage for converted files
Use Wi-Fi for faster conversion of large batches
Solution: Go to Settings > Safari > Camera & Microphone Access and enable
Solution: Check Files app > Downloads folder