# `A2UICore.Formatter.Default`
[🔗](https://github.com/a2ui-elixir/a2ui/blob/v0.1.1/umbrella/apps/a2ui_core/lib/a2ui_core/formatter/default.ex#L1)

The built-in `A2UICore.Formatter`: `en-US` conventions for every locale.

Numbers follow CLDR's `#,##0.###` decimal pattern and `¤#,##0.00`
currency pattern with round-half-even on the shortest decimal form of
the input (so `2.675` rounds to `2.68`, as the reference's decimal
arithmetic does). Alphabetic currency symbols are separated from the
digits by U+00A0 (`CHF 1,234.56`), CLDR's `currencySpacing`.

    iex> A2UICore.Formatter.Default.decimal(1234.567, decimals: 2)
    "1,234.57"
    iex> A2UICore.Formatter.Default.currency(99.99, "USD", [])
    "$99.99"
    iex> A2UICore.Formatter.Default.date(~U[2026-08-26 12:00:00Z], "MMM d, yyyy", [])
    "Aug 26, 2026"

Date patterns are Unicode TR35 patterns: text in single quotes is
literal and `''` is a quote.

    iex> A2UICore.Formatter.Default.date(~U[2026-08-26 19:30:00Z], "EEEE 'at' h:mm a", [])
    "Wednesday at 7:30 PM"

---

*Consult [api-reference.md](api-reference.md) for complete listing*