float_factor

float_factor is a thin subclass of the standard float widget. It overrides exactly two things: the getter that produces the displayed value, and the parser that reads the user's input back.

parse(value) {
    return super.parse(value) / this.props.factor;
}

get value() {
    return this.props.record.data[this.props.name] * this.props.factor;
}

That is the entire widget. Display multiplies, save divides, and the two cancel out so the stored value keeps whatever unit the model intended.

Because the descriptor spreads the float descriptor, it inherits every option the float widget supports and adds factor to the list.

This solves one specific annoyance: the database stores a ratio and people want to read a percentage. A margin stored as 0.35 reads badly on a form. With factor set to 100 it reads as 35, and when someone types 40 the database receives 0.4.

Nobody has to remember to divide. No computed field, no second column, no reporting drift between what the form shows and what the database holds.

The caution is unit confusion. The form now says 35 and the export says 0.35. If your team exports to spreadsheets, tell them once, or they will find it themselves at the worst moment.

A ratio stored as a decimal, shown as a percentage:

<field name="margin" widget="float_factor"
       options="{'factor': 100, 'digits': [16, 2]}"/>

Hours stored as a fraction of a day, shown as hours:

<field name="day_fraction" widget="float_factor"
       options="{'factor': 24}"/>

Omitting factor is legal and does nothing useful, because the default is 1:

<!-- identical to a plain float field -->
<field name="ratio" widget="float_factor"/>

No change. We diffed the float_factor registration between the 19.0 and 20.0 branches: no options added, none removed, same supported types and same component shape.

Note that its sibling float_toggle did change in Odoo 20, gaining a hide_trailing_zeros option. float_factor did not gain it.