Paper Size Converter
Convert dimensions between US Paper sizes (Letter, Legal, Tabloid) and ISO 216 sizes (A4, A3, A5) in inches, mm, and points.
How to Use the Paper Size Converter
- Enter your parameters: Type, paste, or select your input values above.
- View instant results: Calculations update in real time as you change values.
- Copy or export: Click copy, download, or print to use your results immediately.
About this Tool
Compare US Letter (8.5 x 11 in) against ISO A4 (210 x 297 mm) and find exact pixel dimensions at 300 DPI.
NIST Standard Unit Conversion Formula
Target Measurement = Source Measurement * Exact Conversion RatioConversions use official National Institute of Standards and Technology (NIST) reference constants to prevent floating-point drift and guarantee multi-decimal accuracy.
Worked Example: Distance Conversion Example
10.0 US Customary Miles
16.0934 Kilometers (10 * 1.609344)
Calculated using the exact international yard-to-meter definition (1 yard = 0.9144 meters).
Frequently Asked Questions
What is the formula to convert Fahrenheit to Celsius?
Celsius = (Fahrenheit - 32) * (5 / 9). For example, 68°F equals (68 - 32) * (5/9) = 36 * 0.5556 = 20°C.
Are US customary fluid ounces different from British Imperial fluid ounces?
Yes. A US fluid ounce is approximately 29.57 ml, whereas an Imperial fluid ounce is 28.41 ml. TTech uses official US Customary standards with international conversion options.
How many decimal places of precision are maintained?
Calculations maintain full 64-bit IEEE 754 precision and round display outputs to standard significant digits.
Calculation Standards
Derived from NIST Handbook 44 and International System of Units (SI) definitions. For tax, legal, or medical advice, consult certified professionals.
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