PRINT & MAILING REFERENCE
Envelope Size Guide
Search common envelope sizes, compare dimensions visually, and find envelopes that can accommodate cards, letters, brochures, and custom inserts.
ENVELOPE FIT FINDER
What envelope fits my piece?
Choose a common insert or enter a custom finished size. The finder allows adjustable clearance around the insert and checks both orientations.
Fit results are dimensional estimates only. Paper thickness, insert quantity, seams, closures, manufacturing tolerances, and machine-insertion requirements can reduce usable space. Confirm critical jobs with the envelope manufacturer or printer.
VISUAL COMPARISON
Compare envelope sizes to scale
Select up to four envelopes and view them side by side or overlaid from a common corner.
Relative visual only. On-screen physical size depends on the display and browser zoom.
U.S. MAIL DIMENSION REFERENCE
Letter-size dimensional range
USPS letter-size pieces are dimensionally between 5 × 3.5 inches and 11.5 × 6.125 inches, with thickness between 0.007 and 0.25 inch. Other rules can also affect mailability and machinability.
