Convert Peta to Exa

Peta (P) to Exa (E) SI prefix conversion — enter any value below to get an instant result, or use the table for common values.

Results from this calculator are estimates provided for general informational purposes only, based on formulas, rates, and standards commonly accepted as of 2026. Figures may differ slightly from other calculators or professional sources due to rounding methods, differing assumptions, or regional regulations, and rules may change over time. Always consult a qualified professional — such as a financial advisor, healthcare provider, or other relevant specialist — before making decisions based on these results.

Value

From

Result

1 P = 0.001 E

1 Peta = 0.001 Exa

1 Exa = 1000 Peta

1 P in every supported prefix

Conversion chart: Peta to Exa

Conversion table

Peta (P)	Exa (E)
0.01 P	1E-05 E
0.1 P	0.0001 E
1 P	0.001 E
2 P	0.002 E
3 P	0.003 E
5 P	0.005 E
10 P	0.01 E
20 P	0.02 E
50 P	0.05 E
100 P	0.1 E
1000 P	1 E

Peta (P)

Definition: An SI prefix denoting a factor of 10¹⁵ — a quadrillion times the base unit.

History: Adopted by the CGPM in 1975 as part of the same extension that introduced exa-, tera having already proven insufficient for emerging large-scale scientific quantities.

Current use: Widely used in computing (petabytes of storage, petaflops of processing power) and in physics for large energy and frequency quantities.

Exa (E)

Definition: An SI prefix denoting a factor of 10¹⁸ — a quintillion times the base unit.

History: Adopted by the CGPM in 1975, at a time when the largest practical prefixes needed to keep pace with growing quantities in physics and, later, computing.

Current use: Common in describing large-scale computing performance (exaflops) and total global data storage and traffic figures (exabytes).

Supported Units

Prefix	Symbol	Multiplier (× base)
Yotta	Y	1E+24
Zetta	Z	1E+21
Exa	E	1E+18
Peta	P	1E+15
Tera	T	1E+12
Giga	G	1E+09
Mega	M	1000000
Kilo	k	1000
Hecto	h	100
Deka	da	10
None (base unit)	—	1
Deci	d	0.1
Centi	c	0.01
Milli	m	0.001
Micro	µ	1E-06
Nano	n	1E-09
Pico	p	1E-12
Femto	f	1E-15
Atto	a	1E-18
Zepto	z	1E-21
Yocto	y	1E-24

About These Parameters

Value: The number of "From" prefix units you want to re-express in the "To" prefix. Since prefixes are just multiplier scales, this value can represent anything from a physical quantity's leading digits to a plain abstract number.
From Unit: The SI prefix your value is currently scaled by — for example, the "kilo" in "kilogram" or the "nano" in "nanosecond," entered here without the base unit attached.
To Unit: The SI prefix you want the value re-expressed in. Use the swap button to flip From and To instantly, handy when converting a datasheet figure from one prefix scale to another.

How Prefix Conversion Works

The Formula

Every SI prefix is defined by a fixed power-of-ten multiplier relative to the unprefixed base value. To convert a value from one prefix scale to another:

result = value × (multiplier of "From" prefix ÷ multiplier of "To" prefix)

For Peta → Exa: multiply by 0.001. For example, 1 P × 0.001 = 0.001 E.

A History of Powers of Ten

The original six metric prefixes — kilo, hecto, deka, deci, centi, milli — were adopted by the French Academy of Sciences in 1795 alongside the metric system itself. As science and industry needed to describe ever-larger and ever-smaller quantities, the CGPM (Conférence Générale des Poids et Mesures) extended the table repeatedly: mega and micro in 1960 when the modern SI was formalized, giga and nano the same year, tera and pico following soon after, then peta/femto (1975), exa/atto (1975), and finally zetta/zepto and yotta/yocto in 1991 — the classical range covered on this page. In 2022 the CGPM went further still, adding ronna/ronto and quetta/quecto to keep pace with data-storage and astrophysical quantities that had begun to outgrow even yotta.

Why a Prefix-Only Converter Is Useful

Every other unit converter on this site attaches these same prefixes to one specific base unit — grams, watts, bytes, farads — because that's how the prefix is actually used in practice. But the underlying math of "how much bigger is giga than mega" never changes no matter which unit it's modifying, so it's often faster to reason about the prefix scale on its own: quickly checking that a "giga" figure is a billion and not a million, or converting a "nano" measurement from one datasheet into the "micro" scale used by a different one, without needing to know or care what physical quantity either figure describes.

Example

1 P equals 0.001 E. Whatever base unit these prefixes are actually attached to — grams, bytes, watts, seconds — the same multiplier ratio applies: 1 kilo- is always 1,000 times 1 (unprefixed), and 1 mega- is always 1,000 times 1 kilo-, regardless of the quantity being measured.

Frequently Asked Questions

How many Exa are in 1 Peta?

1 Peta (P) equals exactly 0.001 Exa (E).

Is giga a billion or a million?

Giga is always a billion (10⁹) times the base unit — a common point of confusion is with "mega," which is a million (10⁶). The two are frequently mixed up in casual conversation about data storage and computing speed, which is exactly the kind of mistake this converter is designed to catch.

Does this converter work for any unit, like grams or bytes?

Yes — this converter deliberately ignores the underlying unit and works purely with the multiplier scale. "1 kilo- to mega-" gives the same ratio (0.001) whether you mentally attach it to grams, watts, bytes, or any other quantity, because the prefix's multiplier is independent of what it's modifying.

What does "None (base unit)" mean in the unit list?

"None (base unit)" represents a value with no prefix attached at all — a plain gram, meter, or watt rather than a kilogram, kilometer, or milliwatt. It's included so you can convert directly between an unprefixed value and any prefixed scale, such as figuring out how many kilo- units equal one plain (unprefixed) unit.

Are ronna, ronto, quetta, and quecto included here?

Not yet — this page covers the classical SI prefix range from yotta (10²⁴) down to yocto (10⁻²⁴), which was complete from 1991 until 2022. The newer 2022 additions (ronna/ronna-, quetta/quecto) sit beyond even yotta and yocto and aren't included in this table.

Convert Peta to Other Prefixes

Possible Prefix Conversions

Tera to Zetta Nano to Pico Deci to Exa Pico to Exa Hecto to Nano Hecto to Yocto Peta to Hecto Centi to Nano Yocto to Zepto Centi to Zetta Femto to Zetta Zetta to Giga Mega to Zetta Exa to Hecto Micro to Yotta Centi to Giga Yotta to Deka Deka to Zetta Tera to Peta Yocto to None (base unit) Giga to Milli Exa to Zetta Zepto to Yotta Atto to Mega Pico to Hecto Pico to Milli Milli to Atto Atto to Yocto Exa to Pico Tera to Hecto Kilo to Mega Yocto to Yotta Deka to Micro Pico to Nano Tera to Centi Centi to None (base unit) None (base unit) to Deka Mega to Hecto Tera to Atto Deka to Nano Deka to Peta Pico to Deka Exa to Micro Centi to Kilo Zetta to Exa Nano to Milli Hecto to Exa Atto to Zetta Femto to Yotta None (base unit) to Micro Giga to Pico Yocto to Femto Deci to Centi Zepto to Milli Peta to Giga Milli to Hecto Giga to Exa Femto to Atto Giga to Deci Tera to Femto Yotta to Yocto Zetta to Yotta None (base unit) to Yocto Zepto to Atto Deci to Giga Atto to Pico Yocto to Atto Centi to Yotta Zetta to Mega Deci to Yotta Femto to None (base unit) Femto to Mega Exa to Kilo Yotta to Femto Exa to Deci Milli to Micro Peta to Nano Hecto to Yotta Peta to Pico Nano to Centi Kilo to Yocto Exa to Yocto Exa to None (base unit) Mega to Peta Deci to Atto Deci to None (base unit) Deci to Femto Kilo to Micro Deci to Kilo Yocto to Hecto Atto to Micro Kilo to Atto Giga to Nano Kilo to None (base unit) Micro to Hecto Nano to Zepto Hecto to Centi Pico to Yocto Yocto to Kilo Milli to Kilo Zepto to Deci Nano to Micro Femto to Centi Zetta to Deka Zepto to Deka Exa to Yotta Atto to Hecto Zetta to Kilo Milli to Giga Milli to Tera Atto to Kilo Milli to Femto Deka to Kilo Tera to Kilo Yocto to Nano Yocto to Micro Giga to Deka Yotta to Zepto Kilo to Deka Peta to Deka Giga to Hecto Kilo to Pico Pico to Peta Zepto to Kilo Micro to Giga Peta to Deci Tera to Micro Kilo to Centi Yotta to Pico Giga to Kilo None (base unit) to Giga Peta to Milli Yotta to Centi Hecto to Atto Giga to Yocto Pico to None (base unit) Micro to Atto Centi to Zepto Nano to Kilo Nano to Giga Milli to Deci Deci to Yocto Atto to Giga Deci to Hecto Zetta to Deci Milli to Yotta Yocto to Zetta Deka to Femto None (base unit) to Deci Nano to Yotta Micro to Pico Milli to Peta Mega to Giga Kilo to Exa Atto to Zepto Peta to Atto Nano to Deka Zepto to Micro Giga to Zetta Mega to Deka Exa to Deka Centi to Femto Zepto to Nano Pico to Femto Zetta to Tera None (base unit) to Nano Nano to Mega Exa to Nano Zepto to Giga Zetta to None (base unit) Mega to Centi Peta to Mega Yotta to Mega Peta to Centi Deka to Milli Deka to Exa Milli to Zepto Micro to Kilo Femto to Milli Deka to Hecto Zetta to Yocto Yotta to Kilo None (base unit) to Mega Peta to Exa Milli to Exa Hecto to Giga Yocto to Centi Nano to Femto Femto to Kilo Tera to Zepto Micro to Mega Zepto to Zetta Kilo to Deci Zetta to Centi Nano to Atto Deka to Deci Centi to Pico Kilo to Yotta Hecto to Mega None (base unit) to Zetta Atto to Deka Peta to Micro Peta to None (base unit) Hecto to Kilo Atto to Centi Peta to Zetta Tera to Deci Femto to Tera Deci to Micro Centi to Atto Pico to Giga Deka to Pico Giga to Zepto Zepto to None (base unit) None (base unit) to Yotta Yocto to Deci Yotta to Micro Mega to None (base unit) Atto to None (base unit) Atto to Milli Nano to None (base unit) Pico to Zetta Centi to Exa Milli to Deka Exa to Zepto Nano to Peta Peta to Tera Hecto to Deci Tera to Deka Yotta to Milli Atto to Exa Exa to Atto Hecto to None (base unit) Hecto to Zetta Mega to Exa Mega to Zepto Zepto to Hecto Pico to Deci Micro to Peta Micro to Exa Centi to Tera Zepto to Pico Mega to Atto Micro to Yocto Zetta to Nano Yotta to Peta Giga to Mega Centi to Hecto Deci to Milli Micro to Deci Femto to Hecto Giga to Centi Centi to Peta Peta to Zepto Deci to Zetta Tera to Pico Giga to None (base unit) Hecto to Pico Deka to Atto Mega to Tera Milli to Zetta Centi to Deci Milli to Pico None (base unit) to Peta Deka to Centi Yocto to Mega Femto to Micro Kilo to Giga Yotta to Exa Zetta to Peta Yocto to Milli Yotta to Deci Deka to Tera Micro to Femto Hecto to Micro Micro to None (base unit) Pico to Kilo Pico to Micro Deka to None (base unit) Nano to Tera Deka to Yotta Nano to Deci Micro to Zepto Zetta to Zepto Yotta to Hecto Peta to Femto Kilo to Femto Exa to Centi Femto to Nano Kilo to Zepto Milli to Mega Hecto to Milli Zetta to Micro Giga to Atto Mega to Micro Hecto to Tera Tera to Yotta Mega to Milli Hecto to Zepto Femto to Exa Tera to Exa Yocto to Deka Nano to Zetta Giga to Yotta Micro to Deka Yocto to Giga Mega to Pico Mega to Nano Deci to Pico Zepto to Peta Exa to Femto Micro to Zetta Mega to Femto Kilo to Tera Zetta to Hecto None (base unit) to Femto Zepto to Tera Zetta to Pico Micro to Tera Deci to Zepto Zepto to Femto None (base unit) to Atto Atto to Tera Deci to Tera None (base unit) to Hecto Yotta to Tera Yotta to Giga Kilo to Milli Giga to Peta Exa to Tera Zepto to Exa Femto to Yocto Milli to Centi Exa to Mega Centi to Milli Milli to Yocto Deci to Mega Hecto to Femto None (base unit) to Zepto Hecto to Peta Peta to Yotta Nano to Exa None (base unit) to Kilo Kilo to Hecto None (base unit) to Exa Tera to Giga Kilo to Nano Zetta to Femto Yotta to None (base unit) Centi to Yocto Pico to Tera Femto to Zepto Exa to Milli Deka to Giga Zepto to Centi Zepto to Yocto Centi to Mega Kilo to Zetta None (base unit) to Pico Hecto to Deka Giga to Tera Milli to None (base unit) Deka to Mega Zetta to Milli Atto to Femto Atto to Deci Peta to Kilo Centi to Deka Atto to Nano Yocto to Exa Femto to Giga Tera to Mega Pico to Centi None (base unit) to Centi Pico to Atto Deci to Deka Giga to Femto Exa to Peta Yocto to Peta Giga to Micro Pico to Zepto Atto to Peta Pico to Mega Femto to Pico Deka to Zepto Peta to Yocto Tera to None (base unit) Femto to Deka Yotta to Zetta Kilo to Peta Micro to Nano Yotta to Atto Femto to Peta Nano to Yocto Mega to Yocto Micro to Centi Mega to Kilo Mega to Deci Zepto to Mega Yocto to Pico Yotta to Nano Deci to Peta Pico to Yotta None (base unit) to Tera Femto to Deci Nano to Hecto Zetta to Atto Micro to Milli Yocto to Tera Milli to Nano Atto to Yotta Tera to Nano Tera to Yocto Deka to Yocto Centi to Micro Deci to Nano Exa to Giga None (base unit) to Milli Mega to Yotta Tera to Milli