iPhones save photos as HEIC, which many Windows PCs and websites can't open. Add HEIC photos here and download them as JPG, which works everywhere.
HEIC is Apple's default photo format. It keeps quality high at small sizes, but support outside Apple is patchy. On Windows, opening HEIC usually needs extra codec extensions, one of them paid, and many upload forms reject HEIC outright.
This page converts HEIC to JPG at high quality (90) and keeps the original dimensions. You can convert a whole batch and download them as a ZIP.
The conversion happens in your browser. The first HEIC photo takes a moment longer because the converter loads once, then the rest are quick.
Very little at quality 90. Use "Compare" to check. If you need a smaller file, switch to "Under a file size".
Yes. On iPhone go to Settings → Camera → Formats and choose "Most Compatible". New photos will be JPG.
No. They're converted on your device and never sent anywhere.