Letter to A4 Converter
Convert Letter (Letter) to A4 (A4) instantly. 1 Letter = 1 A4.
Paper Size Converter
2 units available
1 Letter = 1 A4
Formula:
A4 = Letter × 1With your value: 1 Letter = 1 A4
Other Letter to A4 conversions
Letter to A4 Conversion Table
| Letter (Letter) | A4 (A4) |
|---|---|
| 0.5 | 0.5 |
| 1 | 1 |
| 2 | 2 |
| 5 | 5 |
| 10 | 10 |
| 15 | 15 |
| 20 | 20 |
| 25 | 25 |
| 50 | 50 |
| 100 | 100 |
| 250 | 250 |
| 500 | 500 |
| 1000 | 1,000 |
A4 to Letter Conversion Table
| A4 (A4) | Letter (Letter) |
|---|---|
| 0.5 | 0.5 |
| 1 | 1 |
| 2 | 2 |
| 5 | 5 |
| 10 | 10 |
| 15 | 15 |
| 20 | 20 |
| 25 | 25 |
| 50 | 50 |
| 100 | 100 |
| 250 | 250 |
| 500 | 500 |
| 1000 | 1,000 |
Where these values come from
Every factor on this page is traced to the document that defines it. See the full provenance dataset or our methodology.
Letter (Letter)
Paper Size
ISO 216 A/B series sizes are defined by a 1:√2 aspect ratio with A0 at one square metre. North American sizes are statutory inch dimensions.
Source: ISO 216:2007, Writing paper and certain classes of printed matter — Trimmed sizes
International Organization for Standardization · Reviewed 2026-07-01
A4 (A4)
Paper Size
ISO 216 A/B series sizes are defined by a 1:√2 aspect ratio with A0 at one square metre. North American sizes are statutory inch dimensions.
Source: ISO 216:2007, Writing paper and certain classes of printed matter — Trimmed sizes
International Organization for Standardization · Reviewed 2026-07-01
How to Convert Letter to A4
To convert from Letter (Letter) to A4 (A4), multiply the value by 1.
Formula: A4 = Letter × 1
Reverse: Letter = A4 × 1
Step-by-Step Example
- Start with your value in Letter. For example: 5 Letter
- Multiply by the conversion factor: 5 x 1
- The result is: 5 A4
About Letter
The letter (Letter) is a unit of paper sizing. One letter equals 1 millimetre of sheet width. UnitConvertLab converts it against every other paper size unit using this exact definition, so results are reproducible to full double precision rather than rounded lookup tables.
Common uses: paper size calculations, engineering and science, education.
About A4
The a4 (A4) is a unit of paper sizing. One a4 equals 1 millimetre of sheet width. UnitConvertLab converts it against every other paper size unit using this exact definition, so results are reproducible to full double precision rather than rounded lookup tables.
Common uses: paper size calculations, engineering and science, education.
Frequently Asked Questions
How many A4 are in 1 Letter?
There are exactly 1 A4 in 1 Letter. This means the conversion factor from Letter to A4 is 1.
What is the formula to convert Letter to A4?
The formula to convert Letter to A4 is: A4 = Letter × 1. For example, to convert 10 Letter to A4, you would multiply 10 by 1.
What is a Letter?
The letter (Letter) is a unit of paper sizing. One letter equals 1 millimetre of sheet width. UnitConvertLab converts it against every other paper size unit using this exact definition, so results are reproducible to full double precision rather than rounded lookup tables.
What is a A4?
The a4 (A4) is a unit of paper sizing. One a4 equals 1 millimetre of sheet width. UnitConvertLab converts it against every other paper size unit using this exact definition, so results are reproducible to full double precision rather than rounded lookup tables.
What are the common uses of Letter?
The Letter is commonly used in paper size calculations, engineering and science, education.
Related Paper Size Conversions
Cite this page
UnitConvertLab. (2026). Letter to A4 converter. UnitConvertLab. Retrieved from https://unitconvertlab.com/convert/paper_letter-to-paper_a4