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Getting Started

Image formats and upload limits

What we accept and how big it can be.

Accepted formats

JPEG, PNG, WebP, GIF, and HEIC/HEIF (the iPhone format) upload from any browser.

If you upload HEIC, we convert it to JPEG in your browser before sending it to our servers. That includes iPhone photos that were saved with a .jpg name, because we check what a file contains rather than what it is called. iPhone photos work the same as anything else.

BMP, TIFF and AVIF are converted to JPEG in your browser too. Safari can convert TIFF; Chrome, Edge and Firefox can't open TIFF files, so in those browsers export the photo as JPEG or PNG first.

A file that isn't really a photo (a PDF renamed to .jpg, for example) is turned away at upload with a message saying so.

Size limits

  • Per file: no hard upper limit, but very large files (50 MB+) will compress aggressively.
  • Auto-compress threshold: anything over 4 MB gets compressed in your browser before upload, to JPEG at 0.85 quality, max 4096×4096. HEIC, BMP, TIFF and AVIF are always converted to JPEG, whatever their size.
  • Upload uses: Web Workers, so the page stays responsive while compressing.

What this means in practice

A typical iPhone shot (~3 MB JPEG) uploads as-is. A 25 MP DSLR raw export (often 12+ MB) gets compressed first. The visual difference is essentially invisible at print or web sizes.

Image quality recommendations

For best AI results:

  • Shoot or export at 4000×3000 or higher when possible.
  • Avoid heavy in-camera HDR or filter presets, which confuse the model.
  • Send the unmodified original if you have one, not a screenshot or downscaled MLS export.

If your only source is a low-resolution image (under 1500 px on the long edge), the result will be technically OK but the AI has less to work with. Exporting the finished edit at 2K or 4K from the Download menu enlarges it, but it cannot add detail the source never had.

Listing portal specs

The limits on this page are what Twilight accepts on upload. Zillow, MLS, Realtor.com and Redfin each have their own size, format and photo-count rules. See Zillow and MLS photo requirements for the portal checklist.