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Plavidian760-666-3130Print and mail production in Vista, California.

Piece Size

Upload a PDF and we'll measure the final print size and tell you whether the piece mails as a USPS Letter or Flat. Uses the same TrimBox-aware sizing logic as our artwork preflight.

Only PDF files are accepted. The first page is measured. If your PDF has a TrimBox set, that defines the final size; otherwise the visible page size is used (which may include bleed).

How the size is detected

  • TrimBox present - uses the TrimBox as the final piece size. This is the most reliable indication and is what production uses.
  • No TrimBox - uses the visible page size. If your PDF includes a 0.125″ bleed and no TrimBox, the reported size will be 0.25″ larger than the final trim in each dimension. We flag this case so you can confirm.
  • Multi-page PDFs - only page 1 is measured. Upload the front side or first sheet.

USPS size categories

  • Letter - at most 6.125″ tall and 11.5″ long. Postcards are letters at a special price: retail (single-piece) cards run 3.5″-4.25″ tall by 5″-6″ long; since July 12, 2026 presorted / automation First-Class cards may run up to 6″ × 9″ when they meet USPS thickness and automation requirements.
  • Flat - exceeds letter limits in at least one dimension but no dimension exceeds 12″ × 15″.
  • Non-standard - smaller than the letter minimum (3.5″ × 5″) or larger than the flat maximum (12″ × 15″). Mails as a parcel or non-machinable piece.