Nowadays, we mainly use two paper size standards in the world. These are the International Standard and the North American Standard.

The International Standard, also known as ISO 216, is used worldwide. As its name suggests, this standard has been adopted by many countries across the globe. The most commonly used paper size in this system is A4. On the other hand, the North American Standard is primarily used in the United States and Canada. This system has its own set of paper sizes that differ from the International Standard.

These two standards show how different parts of the world have developed their own ways of sizing paper. Each has its own history and reasons for use.

ISO International Standard

The story of the ISO International Standard begins in 1786. A German scientist named Georg Christoph Lichtenberg discovered that rectangles with a length-to-width ratio of the square root of two had many special properties.

In the early 20th century, Walter Porstmann applied this concept to create a series of paper sizes. In 1922, this became the German standard known as DIN 476. As more countries started using this system, it eventually became an international standard called ISO 216.

ISO 216 is the international standard for paper sizes defined by the International Organization for Standardization (ISO). Today, most countries in the world use this standard. The well-known A4 paper size comes from this standard.

ISO 216 defines three series of paper sizes: A, B, and C.

The ISO 216 format follows a 1:√2 ratio. This means that when you put two sheets together, they have the same proportions as a single sheet. This feature simplifies many tasks. For example:

• You can shrink two A4 sheets to fit on one A4 sheet
• You can enlarge an A4 sheet to fit on an A3 sheet
• You can enlarge half of an A4 sheet to fill a whole A4 sheet

In all these cases, the paper space is used perfectly, with no waste or shortage.

North American Standard Paper Sizes

The North American paper size system is different from the ISO standard used in most other countries. It's mainly used in the United States and Canada. This system includes several common paper sizes, with the most widely used being Letter, Legal, and Ledger/Tabloid.

Unlike the ISO system, these North American sizes don't follow a single ratio between length and width. This can make scaling between sizes more challenging.

The North American system has been in use for many years and remains the standard in the U.S. and Canada, even as other countries have adopted the ISO system.

Understanding the ABC Series Paper Sizes in a Minute

The international paper sizes are categorized into three distinct groups: A, B, and C. Each series has its own specific dimensions, which are widely used in various applications. Here’s a quick reference table for the sizes:

Specific Applications of the ABC Series Paper Sizes

The ABC series paper sizes are employed in a variety of fields based on their dimensions and specific characteristics:

A Series: The A series is widely used for general document printing, such as books, letters, and reports. The A4 size, in particular, is a standard format for office documents and letters, while larger sizes like A1 and A0 are often used for posters, architectural drawings, and large-format printing.

B Series: The B series sizes are typically used for printing books and magazines where slightly larger or non-standard dimensions are needed. The B5 size is common for personal journals and planners, while B0 and B1 are utilized for large-scale printing projects and technical drawings.

C Series: The C series sizes are mainly used for envelopes and packaging. They are designed to fit the A series documents neatly, with sizes like C4 and C5 being used for different envelope types that accommodate A4 and A5 papers, respectively.

Understanding North American Paper Sizes in a Minute

In North America, paper sizes are typically categorized into three main formats: Letter, Legal, and Ledger/Tabloid. Each of these sizes serves different purposes and is used in various applications. Here’s a quick reference table for these sizes:

Paper Size Table

Specific Applications of North American Paper Sizes

Letter: The Letter size is the most common paper format used in North America. It is widely utilized for everyday office documents such as letters, reports, and memos. This size is ideal for standard correspondence and general printing needs.

Legal: The Legal size paper is primarily used for legal documents, contracts, and detailed forms. Its additional length accommodates more extensive text and legal information, ensuring that documents remain organized and comprehensive.

Ledger/Tabloid: The Ledger/Tabloid size is suited for larger documents like newsletters, brochures, and advertisements. Its broader format is ideal for high-impact graphics, detailed layouts, and presentations that require more space for content.

Differences Between Letter and A4 Paper Sizes

The Letter and A4 paper sizes are often confused due to their similar dimensions, but they have distinct differences:

Letter Size: Commonly used in North America, Letter size measures 216 x 279 mm (8.5 x 11 inches). It is the standard paper size for most office documents, such as letters, reports, and memos.

A4 Size: The A4 size, widely used internationally, measures 210 x 297 mm (8.27 x 11.69 inches). It is a standard format for many types of documents, including business letters, forms, and brochures.

The primary difference between the two is their dimensions. While Letter size is slightly wider and shorter than A4, A4 provides a bit more vertical space. This difference can affect layout and formatting in printing and document preparation.

Which Paper Size Should Your Printer Use?

When choosing a printer, it’s important to select one that accommodates the paper sizes you use most frequently. Many printers offer flexibility, handling multiple paper sizes including Letter and A4.

For those seeking versatility and convenience, Phomemo portable thermal printers are an excellent choice. Available in both A4 and Letter sizes, these printers cater to different needs. Whether you need to print standard documents or larger formats, Phomemo's thermal printers ensure high-quality results with ease. Their compact design also makes them ideal for on-the-go printing, offering a perfect solution for various business and personal applications.

How to Print A4 Documents on Letter Size Paper?

Since Letter paper (8.5 x 11 inches) is slightly shorter in height compared to A4 paper (210 x 297 mm), set the scaling to 94%. This ensures that the A4 document will fit the Letter paper without losing content or distorting the layout.In your print settings, select Letter as the paper size and apply the 94% scaling factor to accommodate the size difference.

How to Print Letter on A4 Size Paper?

Because A4 paper is narrower than Letter paper, you should set the scaling to 97% when printing Letter-sized documents. This adjustment compensates for the 3% width difference between the two paper sizes.Choose A4 as the paper size in your print settings and apply the 97% scaling factor to ensure the Letter document fits well on A4 paper.

Common FAQs

1. What is the difference between A4 and Letter paper?

The difference between A4 and Letter paper primarily lies in their dimensions. A4 paper measures 210 x 297 mm (8.27 x 11.69 inches) and is the standard size used internationally outside North America. In contrast, Letter paper measures 216 x 279 mm (8.5 x 11 inches) and is predominantly used in North America. The key distinctions are that A4 is slightly taller and narrower compared to Letter paper, while Letter paper is marginally wider and shorter. These size differences can affect document layout and formatting, making it important to choose the correct size based on your location and document requirements.

2. What is the A4 paper size used for?

Commonly used for business correspondence, academic papers, reports, and general printing needs in most countries outside North America.

3. What is the Letter paper size used for?

Predominantly used for standard office documents, including letters, memos, reports, and other everyday paperwork in North America.

4. Can I print A4 documents on Letter paper?

Yes, you can print A4 documents on Letter paper. Set the scaling to 94% in your print settings to accommodate the height difference between A4 and Letter sizes.

5. How do I print Letter documents on A4 paper?

To print Letter documents on A4 paper, set the scaling to 97% in your print settings. This adjustment compensates for the width difference between the two sizes.

6. Do Phomemo’s portable printers support both A4 and Letter sizes?

Phomemo’s portable printers are available in separate versions for A4 and Letter sizes, catering to different printing needs.