Formatting

Chilean RUTs are written in various ways. rut-kit lets you normalize any input to the format you need.

Which format to use?

Format	Example	When to use
Default	18972631-7	Store in database
Formatted	18.972.631-7	Display to user
Clean	189726317	Comparisons, external APIs

Format for display

import { formatRut } from 'rut-kit'

const rut = '189726317'
formatRut(rut, 'formatted') // '18.972.631-7'

Format for storage

formatRut('18.972.631-7') // '18972631-7' (default)

Clean dirty data

If you have RUTs from Excel, PDFs, or other sources with unusual separators:

import { cleanRut } from 'rut-kit'

cleanRut('18,972,631-7')  // '189726317'
cleanRut('18*972*631*7')  // '189726317'
cleanRut('33.333.335-k')  // '33333335K'

TIP

cleanRut() is permissive: it removes any character that isn't a digit or K. Ideal for normalizing data before validation.

Calculate check digit

For generating RUTs in tests:

import { getRutCheckDigit } from 'rut-kit'

getRutCheckDigit('18972631') // '7'
getRutCheckDigit('33333335') // 'K'

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See full reference at API rut-kit