# SI and metric prefix converter

> Convert between SI metric prefixes such as giga, mega, kilo, milli, micro and nano, from quecto (10⁻³⁰) to quetta (10³⁰), including the 2022 additions.

النسخة التفاعلية: https://www.calcopenly.com/ar/conversion/si-prefix-converter
الموضوع: محولات الوحدات

An SI prefix multiplies a unit by a power of ten: kilo is 10³, mega 10⁶, milli 10⁻³ and nano 10⁻⁹. Converting between two prefixes multiplies the value by 10 raised to the difference of their exponents, which moves the decimal point without changing any digits. The converter covers all 24 SI prefixes, from quecto (10⁻³⁰) to quetta (10³⁰).

Engineers and students use it to move between scales of one unit. The default turns the 2.4 GHz Wi-Fi band into 2,400 MHz, a shift of three powers of ten. The unit symbol field only labels the result, so the same conversion works for metres, grams, hertz or watts.

Two BIPM rules apply to every prefix: prefixes are never combined (write nm, not mµm), and because the kilogram already carries one, prefixes attach to the gram: 1 mg, not 1 µkg.

## المدخلات

- **القيمة**
- **من** (الخيارات: quetta (Q, 10³⁰), ronna (R, 10²⁷), yotta (Y, 10²⁴), zetta (Z, 10²¹), exa (E, 10¹⁸), peta (P, 10¹⁵), tera (T, 10¹²), giga (G, 10⁹), mega (M, 10⁶), kilo (k, 10³), hecto (h, 10²), deca (da, 10¹), none (10⁰), deci (d, 10⁻¹), centi (c, 10⁻²), milli (m, 10⁻³), micro (µ, 10⁻⁶), nano (n, 10⁻⁹), pico (p, 10⁻¹²), femto (f, 10⁻¹⁵), atto (a, 10⁻¹⁸), zepto (z, 10⁻²¹), yocto (y, 10⁻²⁴), ronto (r, 10⁻²⁷), quecto (q, 10⁻³⁰))
- **إلى** (الخيارات: quetta (Q, 10³⁰), ronna (R, 10²⁷), yotta (Y, 10²⁴), zetta (Z, 10²¹), exa (E, 10¹⁸), peta (P, 10¹⁵), tera (T, 10¹²), giga (G, 10⁹), mega (M, 10⁶), kilo (k, 10³), hecto (h, 10²), deca (da, 10¹), none (10⁰), deci (d, 10⁻¹), centi (c, 10⁻²), milli (m, 10⁻³), micro (µ, 10⁻⁶), nano (n, 10⁻⁹), pico (p, 10⁻¹²), femto (f, 10⁻¹⁵), atto (a, 10⁻¹⁸), zepto (z, 10⁻²¹), yocto (y, 10⁻²⁴), ronto (r, 10⁻²⁷), quecto (q, 10⁻³⁰))
- **Unit symbol**: Only used for labels, e.g. m, g, Hz, W

## النتائج

- القيمة بعد التحويل — النتيجة الرئيسية
- التحويل
- Shift in powers of ten

## الصيغة

$$
x_{\text{to}} = x_{\text{from}} \times 10^{\,e_{\text{from}} - e_{\text{to}}}
$$

## أمثلة محلولة

### 2.4 GHz in MHz

- القيمة: 2.4
- من: giga (G, 10⁹)
- إلى: mega (M, 10⁶)
- Unit symbol: Hz
- **القيمة بعد التحويل: 2,400 MHz**
- **التحويل: 2.4 GHz = 2,400 MHz**
- **Shift in powers of ten: 3**
- مصدر التحقق: ⁨giga = 10⁹, mega = 10⁶ (SI Brochure Table 7): 2.4 × 10³⁩

### 1 km in m

- القيمة: 1
- من: kilo (k, 10³)
- إلى: none (10⁰)
- Unit symbol: m
- **القيمة بعد التحويل: 1,000 m**
- مصدر التحقق: ⁨kilo = 10³⁩

### 1 quetta in yotta (2022 prefix)

- القيمة: 1
- من: quetta (Q, 10³⁰)
- إلى: yotta (Y, 10²⁴)
- Unit symbol: g
- **القيمة بعد التحويل: 1,000,000 Yg**
- **Shift in powers of ten: 6**
- مصدر التحقق: ⁨quetta = 10³⁰ (CGPM 2022), yotta = 10²⁴⁩

### Smallest to largest: quecto to quetta

- القيمة: 1
- من: quecto (q, 10⁻³⁰)
- إلى: quetta (Q, 10³⁰)
- Unit symbol: g
- **Shift in powers of ten: -60**
- **القيمة بعد التحويل: 1 × 10⁻⁶⁰ Qg**
- مصدر التحقق: ⁨10⁻³⁰ / 10³⁰ = 10⁻⁶⁰⁩

### 5 µs in ns

- القيمة: 5
- من: micro (µ, 10⁻⁶)
- إلى: nano (n, 10⁻⁹)
- Unit symbol: s
- **القيمة بعد التحويل: 5,000 ns**
- مصدر التحقق: ⁨micro = 10⁻⁶, nano = 10⁻⁹: 5 × 10³⁩

## الأسئلة

### What are the SI prefixes in order?

There are 24. From largest: quetta (Q, 10³⁰), ronna (R, 10²⁷), yotta (Y, 10²⁴), zetta (Z), exa (E), peta (P), tera (T), giga (G), mega (M), kilo (k, 10³), hecto (h, 10²) and deca (da, 10¹). Then the submultiples: deci (d), centi (c), milli (m, 10⁻³), micro (µ), nano (n), pico (p), femto (f), atto (a), zepto (z), yocto (y), ronto (r) and quecto (q, 10⁻³⁰).

### What are the newest SI prefixes?

Ronna (R, 10²⁷), quetta (Q, 10³⁰), ronto (r, 10⁻²⁷) and quecto (q, 10⁻³⁰), adopted by the 27th General Conference on Weights and Measures (CGPM) in November 2022. They were the first additions since zetta, yotta, zepto and yocto in 1991. On the new scale the Earth's mass, about 5.97 × 10²⁴ kg, is roughly 6 ronnagrams.

### How do I convert between metric prefixes?

Subtract the exponents and move the decimal point that many places. From giga (10⁹) to mega (10⁶) is 9 − 6 = 3 places to the right, so 2.4 GHz = 2,400 MHz; from micro (10⁻⁶) to nano (10⁻⁹) is also 3 places, so 5 µs = 5,000 ns. Moving to a larger prefix shifts the point left: 1,500 m = 1.5 km.

### Why is kilo a lowercase k but mega an uppercase M?

The SI writes the symbols for multiples from mega (M, 10⁶) upward in capitals, while kilo (k), hecto (h), deca (da) and every submultiple are lowercase. The case changes the value: 1 MW (megawatt) is 10⁹ times 1 mW (milliwatt). Writing K for kilo is wrong in the SI, because K is the symbol for the kelvin.

### Does kilo mean 1,000 or 1,024 in computing?

In the SI, kilo always means exactly 1,000, so 1 kbit = 1,000 bits and 1 GB = 10⁹ bytes (NIST). For powers of two the IEC approved binary prefixes in December 1998: 1 KiB (kibibyte) = 1,024 bytes and 1 GiB = 2³⁰ = 1,073,741,824 bytes. The gap grows with size, which is why a 1 TB drive shows about 931 GiB.

### ما مدى دقة «⁨SI and metric prefix converter⁩»؟

تعتمد الدقة على مدخلاتك وافتراضات الطريقة. يستخدم الحساب العشري 50 رقمًا معنويًا، لكن التقديرات والأساليب العددية وبيانات المصدر قد تكون أقل دقة؛ تقريب القيم المعروضة لا يزيل هذه الحدود. أمثلة محلولة جرى التحقق منها بمصادر مستقلة: 5. مثلًا، يجري التحقق من «⁨2.4 GHz in MHz⁩» بالرجوع إلى ⁨giga = 10⁹, mega = 10⁶ (SI Brochure Table 7): 2.4 × 10³⁩.

### ما مصدر هذه الطريقة؟

BIPM — The International System of Units (SI Brochure, 9th ed.), Table 7: SI prefixes; BIPM — CGPM 2022 Resolution 3: ronna, quetta, ronto, quecto.

## المصادر

- [BIPM — The International System of Units (SI Brochure, 9th ed.), Table 7: SI prefixes](https://www.bipm.org/en/publications/si-brochure)
- [BIPM — CGPM 2022 Resolution 3: ronna, quetta, ronto, quecto](https://www.bipm.org/en/cgpm-2022/resolution-3)