#
Display Logic and Input

When creating an Application, it is useful to convert between user-friendly strings (usually displaying ether) and the machine-readable values that contracts and maths depend on (usually in wei).

For example, a Wallet may specify the balance in ether, and gas prices in gwei for the User Interface, but when sending a transaction, both must be specified in wei.

The parseUnits will parse a string representing ether, such as `1.1` into a BigNumber in wei, and is useful when a user types in a value, such as sending 1.1 ether.

The formatUnits will format a BigNumberish into a string, which is useful when displaying a balance.

##
Units

###
Decimal Count

The unit specified may be an integer, which indicates how many decimal place the unit has. For example, 1 ether has 18 decimal places for wei, and if this library were used with Bitcoin, 1 BTC has 8 decimal places for satoshis.

###
Named Units

In addition to specifying unit as a number of decimals, there are several common units, which can be passed in as a string:

- wei — 0
- kwei — 3
- mwei — 6
- gwei — 9
- szabo — 12
- finney — 15
- ether — 18

##
Functions

###
Formatting

utils . commify ( value ) ⇒ string
source

Returns a string with value grouped by 3 digits, separated by `,`.

###
Conversion

utils . formatUnits ( value [ , unit = "ether" ] ) ⇒ string
source

Returns a string representation of value formatted with unit digits (if it is a number) or to the unit specified (if a string).

utils . formatEther ( value ) ⇒ string
source

The equivalent to calling `formatUnits(value, "ether")`.

utils . parseUnits ( value [ , unit = "ether" ] ) ⇒ BigNumber
source

Returns a BigNumber representation of value, parsed with unit digits (if it is a number) or from the unit specified (if a string).

utils . parseEther ( value ) ⇒ BigNumber
source

The equivalent to calling `parseUnits(value, "ether")`.

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