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UtilsNumber

Number utils

import { formatCurrency, formatBytes, clamp } from '@gg-software/utils';

All formatters use Intl.NumberFormat — pass locale in the options to override the runtime default.

numberToString

Number → string, optionally in another base (2–36).

numberToString(42); // "42"
numberToString(255, 16); // "ff"

formatNumber

Locale-aware formatting (thousands separators, decimals). Options are Intl.NumberFormatOptions plus locale.

formatNumber(1234567.891); // "1,234,567.891" (runtime locale)
formatNumber(1234567.891, { locale: 'cs-CZ' }); // "1 234 567,891"
formatNumber(0.5, { maximumFractionDigits: 0 }); // "1"

formatCurrency

Money formatting. currency is a required ISO 4217 code.

formatCurrency(1290, 'CZK', { locale: 'cs-CZ' }); // "1 290,00 Kč"
formatCurrency(19.9, 'EUR', { locale: 'de-DE' }); // "19,90 €"
formatCurrency(5, 'USD', { maximumFractionDigits: 0 }); // "$5"

formatPercent

Percentage formatting — the input is a fraction (0–1).

formatPercent(0.42); // "42%"
formatPercent(0.4251, 1); // "42.5%"
formatPercent(0.42, 0, { locale: 'cs-CZ' }); // "42 %"
ParameterTypeDefault
valuenumber (fraction)—
decimalsnumber0
options.localestringruntime locale

formatBytes

Human-readable file sizes, base 1024 (B, KB, MB, GB, TB, PB).

formatBytes(1536); // "1.5 KB"
formatBytes(10_485_760); // "10 MB"
formatBytes(0); // "0 B"

clamp

Constrain a value to the inclusive [min, max] range.

clamp(15, 0, 10); // 10
clamp(-2, 0, 10); // 0

round

Round to N decimals without the usual floating-point drift.

round(1.005, 2); // 1.01  (naive Math.round gives 1.0)
round(1.2345, 3); // 1.235
round(1.6); // 2
StringDate