Question 1

What are common envelope sizes?

Accepted Answer

DL: 110×220mm (A4 tri-fold). C5: 162×229mm (A4 folded). #10: 105×241mm (US business).

Question 2

What is ISO envelope sizing?

Accepted Answer

C series designed for A series paper. C4 holds A4 flat, C5 holds A4 folded once, C6 holds A4 twice folded.

Question 3

Is this conversion mathematically exact?

Accepted Answer

Yes, this converter uses precise conversion factors based on international standards. Results are accurate to the displayed precision.

Question 4

Can I use this for professional applications?

Accepted Answer

This converter is suitable for educational and general purposes. For critical professional applications, always verify with authoritative sources.

Envelope Size Reference Paper Size Converter - Free Online

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