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Use case · Email

Best File Format for Email Attachments

Email attachments fail for two reasons: the client can’t open the format, or the message exceeds size limits. Pick formats for compatibility first, then shrink.

Quick take: Documents → PDF. Photos → JPG (PNG if transparency). Video → MP4. Bundle → ZIP. Convert niche formats before you hit Send.

Documents

PDF freezes layout across devices. Convert Word/PPT when the recipient only needs to read, not edit.

Images & camera rolls

HEIC from iPhones often frustrates Windows users — convert to JPG. Skip sending huge PNGs of photos when JPG is enough.

Video & archives

Prefer MP4 over MOV. Use ZIP for folders, but compress media first so the archive isn’t enormous.

Key points

  • Compatibility beats niche masters in email.
  • Convert HEIC/MOV before attaching.
  • Shrink before you ZIP.

Convert with Format Convertly

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FAQ

Should I attach DOCX or PDF?

DOCX for collaboration; PDF when layout and “final” reading matter more than editing.

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