Welcome to A4PaperSize.org

A4PaperSize.org provide information and dimensions of current A4 paper size measurements around the world. We strive to keep our visitors up to date with the latest sizes of paper so they can get back to their day to day tasks. Because we understand how important time is, we have laid out our website to accomodate visitor requests.

To get started, simply click one of the four options listed below. If you wish to learn more about paper visit our articles page.

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A4 Paper Size


When did A4 become a standard

A4 became a standard in the late 1970's. However, even though the standards were introduced in the early 20th century, it took more than 50 years for the standard to be recognised world wide.

Which countries use A4

Today, A4 Paper is used by most countries around the world. With the exception of the United States of America and Canada. Many South American countries such as Mexico, Costa Rica, Chile, Venezuela and more, have officially taken on the A4 paper size standard. However, the most common paper size in these countries is still 'Letter Size'.

When to use A4 Size

A4 size is the most common paper standard in the world. It it used for everyday tasks like to-do lists, printing information from a computer, schedules and many other daily tasks.

Who invented paper standards

In the 1920's, Dr Porstmann of Germany published a document proposing a standard for paper which would later change the world. Dr Porstmann's theory quickly became DIN approved, which is a standard in Germany meaning 'Deutsches Institut für Normung'. In English, DIN translates as 'German Institute for Standardisation'.

Why standard measurements were invented

Paper standards were introduced to make life easier for publishers in the 1700's. Different sizes mean different size envelopes, different size letter boxes and unbalanced paper stacks. If paper was never standardised today it would be a lot more expensive, we would need different size fax machines, printers, in and out trays, etc.