A4 paper size

A4 paper size is 8 ¼ x 11 ¾ inches and 210 x 297 millimetres. The general classification of paper is A, B and C. Among these the one widely used is A type and for letterhead and printing it is A4 paper size. These paper come with different sizes all serving variety of purposes. You can know the sizes of these papers from the following charts.

The International Standard of Paper Sizes

Size Millimeter Inches
A0 841 x 1188 33 1/8 x 46 13/16
A1 594 x 841 23 3/8 x 33 1/8
A2 420 x 594 16 ½ x 23 3/8
A3 297 x 420 11 ¾ x 16 ½
A4 210 x 297 8 ¼ x 11 ¾
A5 148 x 210 5 7/8 x 8 ¼
A6 105 x 148 4 1/8 x 5 7/8
A7 74 x 105 2 15/16 x 4 1/8
A8 52 x 74 2 1/16 x 2 15/16

International sizes for envelops

Sizes Millimeter Inches Suitable paper formats
C4 324 x 229 12 ¾ x 9 A3 folded once or flat A4
C5 162 x 229 6 3/8 x 9 A3 folded twice, A4 folded once and flat A5
C6 114 x 162 4 ½ x 6 3/8 A4 folded twice, A5 folded once and flat A6
C7/6 89 x 165 3 ½ x 6 ½ 1/3 A4
DL 110 x 220 4 ¼ x 8 5/8 A4 folded twice or A5 folded once.

Paper sizes in portrait and landscape

A5 paper

Portrait is 148mm in width and 210 mm in height
Landscape is 210 mm in width and 148 mm in height

A4 paper

Portrait is 210 mm in width and 297 mm in height
Landscape is 297 mm in height and 210 mm in width.

A3 paper

Portrait is 297 mm in width and 420 mm in height
Landscape is 420 mm in height and 297 mm in width

A2 paper

Portrait is 420 mm in width and 594 mm in height
Landscape is 594 mm in width and 420 mm in height

A1 paper

Portrait is 594 mm in width and 841 mm in height
Landscape is 841 mm in width and 594 mm in height

A0 paper

Portrait is 841 mm in width and 1189 mm in height
Landscape is 1189 mm in width and 841 mm in width

The ratio of width and height remind the same in A sized paper. This means whether you fold the paper half from the longer side or the wider side the ratio will remain the same which is 1:1.41 and also square root of 2. For example A4 paper size has the dimensions of 210 x 297 mm. If you told it in half it will become A5. Double of A4 becomes A3.
To make it easy to understand the sizes of the papers can be determined by halving them. A0 among the sizes is the biggest one. When you take the half of A0 from it’s longest side it will be A1. Half of A1 is A2. Folding A2 into half will be A3 and then it’s half is A4 paper size. The sizes go in the same pastern all the way to A10. The length of paper that has smaller size is equal to the width of the part with larger size. It is evident in the chart above as well that 297 mm is the length of A4 paper size while the same is the width of A3 paper.
A4 paper size is the paper that is most widely used all around the world including Canada and North America. Be it printing it writing the size of the paper is well adjusted to perform the notable tasked like printing letterheads or used in office work.

Paper sizes from A0 to A10

Paper Height in millimeter Width in millimeter
A0 1189 841
A1 841 594
A2 594 420
A3 420 297
A4 297 210
A5 210 148
A6 148 105
A7 105 74
A8 74 52
A9 52 37
A10 37 26

Standards for paper sizes

ISO 216 standard or ISO A gives the standard to the paper sizes to which A4 paper size is also associated. In 1922 Germany had given the standards for the sizes of paper called DIN 476 and from the same system was the ISO 216 was derived. The size A4 is sometimes also referred to as DIN A4. The Japanese also adopted the same standards of paper sizes and named it as JIS 0138-61 standard.

What is the resolution required to print the picture on A4 size paper?

The pixels are the tinniest fragment on the screen which combined to form a whole picture. The resolution is also calculated in the form of pixels from both the dimensions of length and width. If you want to get a print on the A4 size sheet then you will need to have 2480 x 3508 pixels at 300 pixels per inch. You can have the printing done for seeing or reading at shorter distances like in flyers, brochures, calendars, books and magazines etc.

This resolution works fine in books but if the resolution is kept lower still it gives fine results in low pixel count as well let’s say 250 dots per inch (DPI). Printing required for short distance can have another resolution especially for newspapers images and that is 1240 x 1754 pixel at 150 pixel per inch. Picture printing can even be done from the digital cameras on the A4 size paper which has 8 pixels. Even 6 pixels can give excellent results in printing on A4 papers.
Letter paper size which is used in North America is 8 ½ x 11 inches or 216 x 279 millimetre instead of the A4 paper. This paper is shorter but wider.

ISO 216 standards

The ISO 216 has established a standard for the paper sizes. The ratio of height and width is kept the square root of two which is 1.4142:1. The pages size are kept as the diagonol and sides of a square. In this way a better standard can made for the paper sizes. For example if two A4 paper size are put together or the same page is cut from exact in between from width. The resulting page will also have the same height and width ratio.
The system of the page sizes is also based on the predefined well established metric system. The length and width of the papers of each sides do not make a rounded off figure in metric lengths. The values that are in rounded off form are the area of the pages. These pages are also measured in Mass as grams per meter square. This makes the calculations easy if these pages are to be estimated for knowing the number of pages and format. ISO has decided the simple rules that establish the A series paper.
• In all the forms of A size pages the height is divided by the width. And the answer has to be the square root of two which is 1.4142:1.
• There is one square metre area for A0 format
• The paper A1 is equal to A0 when A1 is cut into two equal pieces. In this way the paper A1 has the height of A0 width. The width of A1 is A0’s height divided in half.
• The A series paper have a simple formula that whatever A series format is it’s height is divided in half (by cutting in equal pieces) and it is converted into the lesser height format. For example the format A4 is cut from width into two pieces and it makes two A5 formats.
• The heights and width of each format of paper is in the rounded off form in millimetres.
B series
Sometimes there are conditions under which the A series are not applicable. There is a need to change the format and therefore the B series is introduced which has brought many other variations in paper sizes.
• The principle of the B series is that the size is the mean of two A series formats. For example the mean of A0 and A1 generates the size of B1. Nevertheless the mean is geometric mean which is different from the arithmetic mean. The arithmetic mean is the sum of two numbers divided by total number (x+y)/2. The geometric mean is the sum of two numbers divided by total number (xy/2). This principle exercises the geometric mean.
• There is introduction of a C series which is for the envelope. The principle for this series is deriving the geometric mean of A and B formats. For exams if you want to fit an A4 paper size then you’ll need a C4 envelop and for ■■■■■■■ a C4 envelop you need to have B4 envelop. If this letter is folded to make an A5 then the letter will fit into a C5 envelop.

In Japan the A series is similar to ISO 216 according to their JIS P 0138-61. Their B series is however different with little variation called either JB or JIS B series. This standard is not international so it is recommended not to use it. You can know and compare well the height and width of the A, B and C format series from the following table

A series Length x width B series Length x width C series Length x width
4A0 1682 x 2378
2A0 1189 x 1682
A0 841 x 1189 B0 1000 x 1414 C0 917 x 1297
A1 594 x 841 B1 707 x 1000 C1 648 x 917
A2 420 x 594 B2 500 x 707 C2 458 x 648
A3 297 x 420 B3 353 x 500 C3 324 x 458
A4 210 x 297 B4 250 x 353 C4 229 x 324
A5 148 x 210 B5 176 x 250 C5 162 x 229
A6 105 x 148 B6 125 x 176 C6 114 x 162
A7 74 x 105 B7 88 x 125 C7 81 x 114
A8 52 x 74 B8 62 x 88 C8 57 x 81
A9 37 x 52 B9 44 x 62 C9 40 x 57
A10 26 x 37 B10 31 x 44 C10 28 x 40

Applications of formats

ISO has established very definitive measures for paper sizes but not all of these are in common practice except for A4 being the most popular. Below is the table to tell the common usage of these formats.

A8, B8 Playing cards
A3, B4 Newspapers. Used in the photocopying machine other than A4
C6, C5, C4 Envelops for the A4 letter. No fold C4, one fold C5 and two folds C6
A6, B6, A5, B5 Books
A6 Postcards
A5 Notepads
A4 Used in photocopying machines, laser printing, catalogs, forms, magazines, letters
A3, A2 Large tables, diagrams, drawings
A2, A1 Flip charts
A1, A0 Posters, technical drawings

The common purpose that A4 serves is in photocopying. Sometimes it happens that you want to change the format of the papers you want to photocopy. Therefore the machines come with the enhancements of changing the magnification factor to the desired adjustments and also to shift the formats. For example you want to save the paper by printing the journal on an A4 format to two journals on A3 format. For this you should either do the settings of magnification factor into 71% or if the machine has the function of converting A4 to A3 then simply give the input

The common purpose that A4 serves is in photocopying. Sometimes it happens that you want to change the format of the papers you want to photocopy. Therefore the machines come with the enhancements of changing the magnification factor to the desired adjustments and also to shift the formats. For example you want to save the paper by printing the journal on an A3 format to two journals on A4 format. For this you should either do the settings of magnification factor into 71% or if the machine has the function of converting A3 to A4 then simply give the input. Now the print you will have two A4 pages with the journal equally divided on both the sheets with no text cutting it margin space wasting. You can also apply the same principle for the books in A5 or B5 format.
You can quickly apply the magnification factor upon the copying machines from the following key

71% Square root (0.5) A3 to A4
84% Square root of (square root 0.5) B4 to A4
119% Square root of (square root 2) A4 to B4 or B5 to A4
141% Square root 2 A4 to A3 or A5 to A4

The magnification factors between all A series sizes are as follows

A0 A1 A2 A3 A4 A5 A6 A7 A8 A9 A10
A0 100 71 50 35 25 18 12.5 8.8 6.2 4.4 3.1
A1 141 100 71 50 35 25 18 12.5 8.8 6.2 4.4
A2 200 141 100 71 50 35 25 18 12.5 8.8 6.2
A3 283 200 141 100 71 50 35 25 18 12.5 8.8
A4 400 283 200 141 100 71 50 35 25 18 12.5
A5 566 400 283 200 141 100 71 50 35 25 18
A6 800 566 400 283 200 141 100 71 50 35 25
A7 1131 800 566 400 283 200 141 100 71 50 35
A8 1600 1131 800 566 400 283 200 141 100 71 50
A9 2263 1600 1131 800 566 400 283 200 141 100 71
A10 3200 2263 1600 1131 800 566 400 283 200 141 100

All figures are in percentages. The basic formula is to have the 1:square root of 2 in ISO paper format. It not only implies on the photocopying machines in libraries and offices but also printing, microfilming and repro photography.


Paper weight is also one important aspect in the ISO because you sometimes have to send the documents through mail and the weight calculations can determine the charges of the courier. ISO paper series makes it very convenient. The laser printing and typewriter type of paper usually weighs 80 grams per meter square. The area of A0 paper is 1 meter square. The next smaller size in the series will have an area half of it. This makes the area of A4 bring 1/16th meter square to A0 and a weight of 5 grams. A C4 envelop for securing the document will have 20 grams. So to make a total of 100 grams for the minimal postal fee the number of pages in a C4 envelop should be 16. This is the advantage of the metric system based paper sizes that they make the calculations easy even in packed papers, newspapers and books.
Using these standard sizes can only render convenience. It will be much easier for the libraries to have the same sizes binders designated for the respective paper sizes. The books or journals arranged in the shelves can have a unanimity . Apart from being utilized in the offices for different purposes the ISO standard sizes serve some other interesting purposes. In few countries like Germany there are some brands that have the A6 format size for toilet papers, the library microfiches deploy A6 size, B7 format is used in passports in European Union and US and the I’d card for German citizens is in B7 format.


This is one standard that was meant to serve many purposes. There are still countries that have some exception in following the ISO 216 rules. These principles were established after much of contemplation. If everyone follows the same rules then universally documents, books, magazines will be in one standard form sparing people from off the region from the confusion and hard-working of calculations. The best thing about the system is that it is not random. Rather it is based on the metric system. The same system prevalent around the world for precision measurements of different physical qualities. No one can aim that the system has flaws. The standards are well calculated and precisely define the basic purposes. You can easily utilize then in printing or writing purposes with pre estimated sizes.

History of papermaking

Paper is being in use from centuries for transferring information and communicating. Other uses may involve photography, insulation, toweling, packaging and wrapping. The basic method in papermaking is to dissolve the cellulose in water and a sheet is made in a wire screen. The word paper was derived from the term papyrus. This is reedy tree that grows in large numbers in Egypt along river Nile. Anciently paper was formed by taking fiber from this tree and criss crossing it’s layers. These layers were then pressed while being damp. The layers glued with each other due to the sticky cell sap. This was the widely used writing material which is still found in many scriptures found from the ancient times.

History of development of papermaking

Paper is being in use from centuries for transferring information and The first traces of papermaking were found in 105 AD when the China’s Imperial court created paper from materials like ■■■■ wastes, old rags, fishnets, ■■■■ fibers and mulberry. The formation of paper slowly and gradually moved towards Samarkand in 751 AD. The first paper production was in the golden era of Haroon ur Rashid in 793 AD. This forwarded the process further to Europe.
It was by 14th century that there were numerous paper Mills seen in Europe in Germany, Spain, France and Italy. The demand of paper was increased slot after printing came into being in 1450. Till the 18th century the basic raw material were cotton rags and linen. There was a constant shortage of the raw material rags that they were even publicized to fulfill the need. It was becoming evident that a replacement of the raw material was required with something found more readily in larger quantities.

New materials and process

A book got published in 1800 which for the first time gave the practical method of manufacturing paper from wood pulp or other vegetal pulps. The paper industry flourished by the use of wood pulp as raw material the demand was also covered. There were two methods involved in this process. In the first process the mechanical method was used to separate the fibers and it’s fragments. The other process was that of chemical usage to separate wood pulp from liginin and other components. The mechanical method thus does not purify the wood that we’ll thus not giving high quality white paper. Permanence, and whiteness can be attained by wood pulp when there is use of chemicals like sulfite pulp and soda.
The paper that is manufactured from the cellulose us water absorbent. The water based ink when used over it will not only absorbent it but also will spread. To prevent this and make paper more impregnant is called sizing. Till the 18th century expensive materials like vegetable gums and animal glues were used for impregnation. Later in the same century the method was improved by introduction of using alum and rosin for sizing. Chlorine was being employed as a method of bleaching the paper but it formed low quality paper because of low chemical knowledge. However chlorine is still used as a bleaching agent in paper production.

Paper machinery development

In the beginning there was a single sheet of paper that was made by using a frame and the sheets were pressed to drain off the water. In 1798 the first of its kind paper machinery was introduced in which there were a number of sheets produced in a continuous manner and they were dried by squeezing off the water by passing them from rollers. The paper machine very was not in a very developed form though. An improved version of the same machine was made in England which also got patented. Paper machinery evolved slowly and gradually into the paper industry we see today. It also became more mechanized with time which reduced the hand labour.


The pattern that is followed by the paper industry for A4 paper size and rest is still the same. The mechanization and designing involved in the process is the most important aspect of the industry. Many changes have occurred since the advent of paper making industry. There are some processes that make the core of the industry and are still the same. First the cellulose is suspended in water and mixed thoroughly that it becomes saturated with water. This mixture is then spread over a sheet where it is distilled and a sheet of matted fiber is formed. The sheets are pressed to remove the water. The leftover water removes through evaporation. Next step is that as per the requirement of material the paper is impregnated and dried. The difference in the quality depends upon type of pulp or fiber, the extent of refining or more precisely called beating, adding different materials to the beaten stocks and the kind of physical or chemical additions to the paper at the end. This is the story of paper formation for A4 paper sizes and the rest of formats. All the classifications have been done for the purpose of making it convenient to communicate in academic and office work the size of paper or envelop is required. So wherever in the world you have to send the letter or other documents then your assessment for paper will be easy to understand. The

Frequently Asked Questions

1. What is A4 size in centimeters?

The dimensions of A4 paper size in centimeters is 210 x 297.

2. Is A4 size as equal to 8.5 x 11?

No the sizes are different. The standard A4 paper size is different from USA 8.5 x 11 inches size in both the dimensions of length and width. A4 paper size is longer and narrower. In inches A4 size is 8.27 x 11.69.

3. Is an A4 size 8 x 10?

The standard size for A4 sheets according to ISO is 210 x 297 millimeters. The British version is called Quarto which has the nearest size of 8 x 10 inches.

4. Why is A4 size called so?

The standard of each size is A0 is the A series. It depends upon the size it has which is in square meters although the shape is not square. The A4 paper size sheet is used for writing because it is easier to use this sheet than the square metre sheet.

5. Is A4 size the standard size?

The standard size of paper can be considered as the A4 paper size. Although the standard of sizes is established by ISO and all of them are in some kind of use but A4 paper size is commonly used in printing and writing. The wide utility of the paper can make it a standard.

6. Why is there a different paper size in US?

The whole of Europe uses the ISO standard that is based on the square root of two. The US has not yet adopted the standard for unknown reason so their A4 is not a standard size.

7. What is 8.5 x 11 size paper called?

The 8.5 x 11 inches paper size is called the letter and this classification is mostly used in academics and offices. The other forms are 11 x 17 inches Tabloid, 8.5 x 14 inches Legal and then 8.5 x 11 inches Letter.

8. Which is more preferred A4 or Letter?

If you are dealing with someone outside US or Canada then keep the standard for using A4. But for the US and Canada clientele it’s better to use Letter.

9. Where is A4 used?

Theist common use of A4 paper size is in printing. A5 has many other utilities and it the best choice for booklets, flyers, invitations, diaries and planners.

10. What is bigger A4 or A5?

A4 is 297 x 210 millimeter and A5 is 210 x 148 millimeters. So A4 is bigger in size. The formats progress from A10 to A0 in sizes. A10 being the smallest and A0 being the biggest.

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