Decimal Point & Thousands Separators

Notes Calculator reads numbers written with thousands separators the same way it shows them, so you can type — or paste back — a grouped number like 1.234.567 and get its value.

Which character is the decimal point and which is the thousands separator is controlled by the Use dot as decimal point setting.

The two conventions

Setting	Decimal point	Thousands separator	Example input	Value
Off	`,` comma	`.` dot	`1.234.567,89`	1234567.89
On	`.` dot	`,` comma	`1,234,567.89`	1234567.89

With the setting off — comma is the decimal point, dot groups the thousands:

1.234.567                              | 1.234.567
1.234.567,89                           | 1.234.567,89
18,5                                   | 18,5
2 * 1.234.567                          | 2.469.134

With Use dot as decimal point turned on — dot is the decimal point, comma groups the thousands:

1,234,567                              | 1,234,567
1,234,567.89                           | 1,234,567.89
18.5                                   | 18.5

It starts from your device’s region

There is no fixed default any more. Until you pick a side, the setting follows the region your device formats numbers in:

A United States, United Kingdom, Indian, Japanese, Chinese or Korean region starts with the dot as the decimal point.
A German, Italian, French, Spanish, Brazilian or Dutch region starts with the comma.
The region wins over the language. English with an Italian region gets the comma, because that is how macOS and iOS format numbers there.
If the region can’t be recognised, the comma is used.

Choosing the setting yourself always wins over the region, and the lines you already wrote are re-read straight away. If you are signed in, your choice is remembered for the account, so every device you use shows the same separator.

Rules

Thousands groups are three digits each (the leading group may be 1–3). A well-formed number like 1.234.567 is read as 1234567; a malformed one like 1.2.3 is not a valid grouped number and is simply ignored (the line stays blank).
A single group counts too. With the comma as the decimal point, 1.500 is one thousand five hundred, not one and a half — write 1,5 for one and a half. So 2.391 - 2.298 is 93:

2.391 - 2.298                          | 93
1.234 + 1                              | 1.235

Only a genuine group is grouped. Everything else stays a decimal:

You type (comma as decimal point)	Read as
`2.391`	2391 — a well-formed three-digit group
`3.14`	3.14 — the tail isn’t three digits
`0.001`	0.001 — a group never starts with a zero
`1.500e3`	1500 — the exponent already scales the number
`2,391`	2.391 — comma is the decimal point

The same holds mirrored when Use dot as decimal point is on: 2,391 is 2391, 2.391 stays 2.391, 0,001 is 0.001, and 1,500e3 is 1500.

Underscores for readability

You can also group the digits of a whole number with underscores — the same trick many programming languages use. Underscores are purely visual, so they work the same way whatever your decimal-point setting is:

1_000_000                              | 1.000.000
123_456_789                            | 123.456.789
2 * 1_000                              | 2.000

An underscore has to sit between two digits — a leading, trailing, or doubled underscore (_1000, 1000_, 1__000) isn’t a valid number, so the line just stays blank. Underscores group the whole-number part only; they aren’t read inside the decimal part or an exponent.

Inside functions, commas separate arguments

A comma is also how you separate function arguments, so a comma inside a function call is treated as an argument separator — not a thousands group:

sum(100, 200, 300)                     | 600

With Use dot as decimal point on, sum(1,234,567) is therefore read as the three arguments 1, 234, 567 (which sum to 802), not as one grouped number. To pass a grouped number as a single argument, wrap it in parentheses:

sum((1,234,567), 3)                    | 1,234,570