The DL envelope is shortened for the term ‘Dimension Lengthwise’, due to its longer aspect ratio than the standard envelope. DL was previously known and a shortened version for DIN Lang in Germany, which was where this envelope size originated from in the 1920’s.
‘Din’ is the German Institute for Standardisation Registered Association, which is the acknowledged national standards that represents German interest in European and international standard organisations. The ‘L’ in ‘DL’ means ‘lang’, which in English means ‘long’, as the DL envelope is a wider aspect ratio, compared to other envelopes.
DL Envelopes are one of the most popular sizes used within business, and is 220 x 110mm in size, which is an A4 sheet of paper folded into thirds.