Validate phone numbers in Ruby

The plans in this file

Add the countries whose numbers you accept; the file and its tests below are generated again for them, in your browser.

• United Kingdom +44×
• United States +1×
• France +33×

1. The plans

PLANS holds one entry per plan: its region (the ISO code), the country code, the trunk prefix dialled before a national number, the exit code dialled before an international one, and a pattern per line type. The patterns are the plans' own, anchored, in the order the file tries them: the special ranges first (premium rate, toll-free, shared cost, VoIP, personal, pager, UAN, voicemail), then fixed line, then mobile. A plan that names no single exit code gets an empty one, and calls out of it use the + form.

# frozen_string_literal: true

# phone.rb: validate, normalise and dial phone numbers with the national numbering plans.
# Plans: GB +44, US +1, FR +33 (data as of 2026-10-25).
# Other plans: https://phonelookup.dev/guides/validate-phone-numbers-ruby?plans=gb,us,fr
# Each pattern matches a national significant number: digits only, no country code, no trunk prefix.
module Phone
  # One numbering plan: region, country code, trunk prefix, exit code and an anchored pattern per line type.
  Plan = Struct.new(:region, :cc, :trunk, :exit_code, :types, keyword_init: true)

  # A number as read: E.164, the plan it belongs to, its line type, country code and national number.
  Number = Struct.new(:e164, :region, :type, :cc, :nsn, keyword_init: true)

  PLANS = [
    Plan.new(
      region: "GB", cc: "44", trunk: "0", exit_code: "00",
      types: {
        "premiumRate" => /\A(?:(?:8(?:4[2-5]|7[0-3])|9(?:[01]\d|8[2-49]))\d{7}|845464\d)\z/,
        "tollFree" => /\A(?:80[08]\d{7}|800\d{6}|8001111)\z/,
        "voip" => /\A(?:56\d{8})\z/,
        "personalNumber" => /\A(?:70\d{8})\z/,
        "pager" => /\A(?:76(?:464|652)\d{5}|76(?:0[0-28]|2[356]|34|4[01347]|5[49]|6[0-369]|77|8[14]|9[139])\d{6})\z/,
        "uan" => /\A(?:(?:3[0347]|55)\d{8})\z/,
        "fixedLine" => /\A(?:(?:1(?:1(?:3(?:[0-58]\d\d|73[0-5])|4(?:(?:[0-5]\d|70)\d|69[7-9])|(?:(?:5[0-26-9]|[78][0-49])\d|6(?:[0-4]\d|5[01]))\d)|(?:2(?:(?:0[024-9]|2[3-9]|3[3-79]|4[1-689]|[58][02-9]|6[0-47-9]|7[013-9]|9\d)\d|1(?:[0-7]\d|8[0-3]))|(?:3(?:0\d|1[0-8]|[25][02-9]|3[02-579]|[468][0-46-9]|7[1-35-79]|9[2-578])|4(?:0[03-9]|[137]\d|[28][02-57-9]|4[02-69]|5[0-8]|[69][0-79])|5(?:0[1-35-9]|[16]\d|2[024-9]|3[015689]|4[02-9]|5[03-9]|7[0-35-9]|8[0-468]|9[0-57-9])|6(?:0[034689]|1\d|2[0-35689]|[38][013-9]|4[1-467]|5[0-69]|6[13-9]|7[0-8]|9[0-24578])|7(?:0[0246-9]|2\d|3[0236-8]|4[03-9]|5[0-46-9]|6[013-9]|7[0-35-9]|8[024-9]|9[02-9])|8(?:0[35-9]|2[1-57-9]|3[02-578]|4[0-578]|5[124-9]|6[2-69]|7\d|8[02-9]|9[02569])|9(?:0[02-589]|[18]\d|2[02-689]|3[1-57-9]|4[2-9]|5[0-579]|6[2-47-9]|7[0-24578]|9[2-57]))\d)\d)|2(?:0[013478]|3[0189]|4[017]|8[0-46-9]|9[0-2])\d{3})\d{4}|1(?:2(?:0(?:46[1-4]|87[2-9])|545[1-79]|76(?:2\d|3[1-8]|6[1-6])|9(?:7(?:2[0-4]|3[2-5])|8(?:2[2-8]|7[0-47-9]|8[3-5])))|3(?:6(?:38[2-5]|47[23])|8(?:47[04-9]|64[0157-9]))|4(?:044[1-7]|20(?:2[23]|8\d)|6(?:0(?:30|5[2-57]|6[1-8]|7[2-8])|140)|8(?:052|87[1-3]))|5(?:2(?:4(?:3[2-79]|6\d)|76\d)|6(?:26[06-9]|686))|6(?:06(?:4\d|7[4-79])|295[5-7]|35[34]\d|47(?:24|61)|59(?:5[08]|6[67]|74)|9(?:55[0-4]|77[23]))|7(?:26(?:6[13-9]|7[0-7])|(?:442|688)\d|50(?:2[0-3]|[3-68]2|76))|8(?:27[56]\d|37(?:5[2-5]|8[239])|843[2-58])|9(?:0(?:0(?:6[1-8]|85)|52\d)|3583|4(?:66[1-8]|9(?:2[01]|81))|63(?:23|3[1-4])|9561))\d{3})\z/,
        "mobile" => /\A(?:7(?:457[0-57-9]|700[01]|911[028])\d{5}|7(?:[1-3]\d\d|4(?:[0-46-9]\d|5[0-689])|5(?:0[0-8]|[13-9]\d|2[0-35-9])|7(?:0[1-9]|[1-7]\d|8[02-9]|9[0-689])|8(?:[014-9]\d|[23][0-8])|9(?:[024-9]\d|1[02-9]|3[0-689]))\d{6})\z/,
      }.freeze
    ),
    Plan.new(
      region: "US", cc: "1", trunk: "1", exit_code: "011",
      types: {
        "premiumRate" => /\A(?:900[2-9]\d{6})\z/,
        "tollFree" => /\A(?:8(?:00|33|44|55|66|77|88)[2-9]\d{6})\z/,
        "personalNumber" => /\A(?:52(?:3(?:[2-46-9][02-9]\d|5(?:[02-46-9]\d|5[0-46-9]))|4(?:[2-478][02-9]\d|5(?:[034]\d|2[024-9]|5[0-46-9])|6(?:0[1-9]|[2-9]\d)|9(?:[05-9]\d|2[0-5]|49)))\d{4}|52[34][2-9]1[02-9]\d{4}|5(?:00|2[125-9]|3[23]|44|66|77|88)[2-9]\d{6})\z/,
        "fixedLine" => /\A(?:983[2-57-9]\d{6}|(?:2(?:0[1-35-9]|1[02-9]|2[03-57-9]|3[1459]|4[08]|5[1-46]|6[0279]|7[02469]|8[13])|3(?:0[1-57-9]|1[02-9]|2[013-79]|3[0-24679]|4[167]|5[0-3]|6[01349]|8[056])|4(?:0[124-9]|1[02-579]|2[3-5]|3[0245]|4[023578]|58|6[349]|7[02589]|8[04])|5(?:0[1-57-9]|1[0235-8]|20|3[0149]|4[01]|5[179]|6[1-47]|7[0-5]|8[0256])|6(?:0[1-35-9]|1[024-9]|2[03689]|3[016]|4[0156]|5[01679]|6[0-279]|78|8[0-269])|7(?:0[1-46-8]|1[2-9]|2[04-8]|3[0-2478]|4[0378]|5[47]|6[02359]|7[0-59]|8[156])|8(?:0[1-68]|1[02-8]|2[0168]|3[0-2589]|4[03578]|5[046-9]|6[02-5]|7[028])|9(?:0[1346-9]|1[02-9]|2[0589]|3[0146-8]|4[01357-9]|5[12469]|7[0-3589]|8[04-69]))[2-9]\d{6})\z/,
        "mobile" => /\A(?:983[2-57-9]\d{6}|(?:2(?:0[1-35-9]|1[02-9]|2[03-57-9]|3[1459]|4[08]|5[1-46]|6[0279]|7[02469]|8[13])|3(?:0[1-57-9]|1[02-9]|2[013-79]|3[0-24679]|4[167]|5[0-3]|6[01349]|8[056])|4(?:0[124-9]|1[02-579]|2[3-5]|3[0245]|4[023578]|58|6[349]|7[02589]|8[04])|5(?:0[1-57-9]|1[0235-8]|20|3[0149]|4[01]|5[179]|6[1-47]|7[0-5]|8[0256])|6(?:0[1-35-9]|1[024-9]|2[03689]|3[016]|4[0156]|5[01679]|6[0-279]|78|8[0-269])|7(?:0[1-46-8]|1[2-9]|2[04-8]|3[0-2478]|4[0378]|5[47]|6[02359]|7[0-59]|8[156])|8(?:0[1-68]|1[02-8]|2[0168]|3[0-2589]|4[03578]|5[046-9]|6[02-5]|7[028])|9(?:0[1346-9]|1[02-9]|2[0589]|3[0146-8]|4[01357-9]|5[12469]|7[0-3589]|8[04-69]))[2-9]\d{6})\z/,
      }.freeze
    ),
    Plan.new(
      region: "FR", cc: "33", trunk: "0", exit_code: "00",
      types: {
        "premiumRate" => /\A(?:836(?:0[0-36-9]|[1-9]\d)\d{4}|8(?:1[2-9]|2[2-47-9]|3[0-57-9]|[569]\d|8[0-35-9])\d{6})\z/,
        "tollFree" => /\A(?:80[0-5]\d{6})\z/,
        "sharedCost" => /\A(?:8(?:1[01]|2[0156]|4[024]|84)\d{6})\z/,
        "voip" => /\A(?:9\d{8})\z/,
        "uan" => /\A(?:80[6-9]\d{6})\z/,
        "fixedLine" => /\A(?:(?:26[013-9]|59[1-35-9])\d{6}|(?:[13]\d|2[0-57-9]|4[1-9]|5[0-8])\d{7})\z/,
        "mobile" => /\A(?:(?:6(?:[0-24-8]\d|3[0-8]|9[589])|7[3-9]\d)\d{6})\z/,
      }.freeze
    ),
  ].freeze

2. Reading a number

Phone.parse keeps the digits and a leading plus. With the plus, or with the default region's exit code in front (00 from the United Kingdom, 011 from the United States), the first one to three digits are the country code: under ITU-T E.164 no code is the prefix of another, so at most one length names a plan, and the plans sharing a code (+1, +7, +44) are tried in turn. Without either, the number is national and is read in the default region's plan. The trunk prefix is tried stripped first, so “+44 (0)7400 123456” reads too. A number in both the fixed-line and the mobile ranges comes back as fixedLineOrMobile, which is every ordinary number in the +1 plans. Digits typed in other scripts are dropped with the punctuation; convert them first if your users type them. Anything no plan accepts gives nil.

  # Reads a number the way people type it: "+44 7400 123456", "07400 123456", "00 44 7400 123456".
  # A number without + or an exit code is read in the plan of default_region (an ISO code such as "GB").
  # Returns nil when no plan in PLANS accepts it.
  def self.parse(text, default_region = nil)
    s = text.to_s.gsub(/[^0-9+]/, "")
    digits = s.delete("+")
    return nil unless (3..17).cover?(digits.length)
    return international(digits) if s.start_with?("+")

    home = PLANS.find { |plan| plan.region == default_region }
    return nil unless home
    if !home.exit_code.empty? && digits.start_with?(home.exit_code)
      return international(digits.delete_prefix(home.exit_code))
    end

    match([home] + PLANS.select { |plan| plan.cc == home.cc && !plan.equal?(home) }, digits)
  end

  # Country codes are prefix-free (ITU-T E.164): the first one to three digits that name a plan are the code.
  def self.international(digits)
    (1..[3, digits.length].min).each do |size|
      plans = PLANS.select { |plan| plan.cc == digits[0, size] }
      return match(plans, digits[size..]) unless plans.empty?
    end
    nil
  end

  # The trunk prefix is tried stripped first: "+44 (0)7400 123456" is common.
  def self.match(plans, nsn)
    plans.each do |plan|
      tries = !plan.trunk.empty? && nsn.start_with?(plan.trunk) ? [nsn.delete_prefix(plan.trunk), nsn] : [nsn]
      tries.each do |national|
        type = type_of(plan, national)
        return Number.new(e164: "+#{plan.cc}#{national}", region: plan.region, type: type, cc: plan.cc, nsn: national) if type
      end
    end
    nil
  end

  # The first matching type wins; a number in both the fixed-line and the mobile ranges is reported as such.
  def self.type_of(plan, nsn)
    hits = plan.types.select { |_, pattern| pattern.match?(nsn) }.keys
    return nil if hits.empty?

    hits.first == "fixedLine" && hits.include?("mobile") ? "fixedLineOrMobile" : hits.first
  end
  private_class_method :international, :match, :type_of

3. Writing and dialling it

Store the E.164 form, a plus and digits only: one string per number, and every other format follows from it.Phone.to_tel writes the tel: URI for links (RFC 3966). Phone.dial_from gives the digits a person dials from another country: the caller's exit code, the country code and the national number, or, between plans that share a country code, a national call with the trunk prefix. The dialling helper explains each case.

  # The tel: URI (RFC 3966), for links.
  def self.to_tel(number)
    "tel:#{number.e164}"
  end

  # What to dial from a phone in from_region. Inside one country code (the UK and Jersey, the US and Canada)
  # the call is dialled like a national one, with the trunk prefix; otherwise the exit code, the country code
  # and the national number. The + form when from_region is not in PLANS or its plan names no exit code.
  def self.dial_from(number, from_region)
    from = PLANS.find { |plan| plan.region == from_region }
    return number.e164 unless from
    return from.trunk + number.nsn if from.cc == number.cc

    from.exit_code.empty? ? number.e164 : from.exit_code + number.cc + number.nsn
  end
end

The tests

The cases are the plans' own example numbers, one per line type in international form; the first plan's mobile number again in national form, with “(0)”, and dialled with an exit code; then numbers no plan accepts, and three calls dialled. Their expected values are computed when the page is built, by the same logic in TypeScript. The generator behind this page is checked by running its output in minitest (ships with Ruby), for these plans and for all 245 plans at once.

ruby phone_test.rb

# frozen_string_literal: true

require "minitest/autorun"
require_relative "phone"

class PhoneTest < Minitest::Test
  def test_reads_each_line_type_of_each_plan
    [
      # typed, default region, E.164, line type
      ["+44 7400 123456", nil, "+447400123456", "mobile"],
      ["+44 121 234 5678", nil, "+441212345678", "fixedLine"],
      ["+44 800 123 4567", nil, "+448001234567", "tollFree"],
      ["+44 56 1234 5678", nil, "+445612345678", "voip"],
      ["+44 901 234 5678", nil, "+449012345678", "premiumRate"],
      ["+44 70 1234 5678", nil, "+447012345678", "personalNumber"],
      ["+44 76 4012 3456", nil, "+447640123456", "pager"],
      ["+44 55 1234 5678", nil, "+445512345678", "uan"],
      ["+1 201-555-0123", nil, "+12015550123", "fixedLineOrMobile"],
      ["+1 800-234-5678", nil, "+18002345678", "tollFree"],
      ["+1 900-234-5678", nil, "+19002345678", "premiumRate"],
      ["+1 500-234-5678", nil, "+15002345678", "personalNumber"],
      ["+33 6 12 34 56 78", nil, "+33612345678", "mobile"],
      ["+33 1 23 45 67 89", nil, "+33123456789", "fixedLine"],
      ["+33 801 23 45 67", nil, "+33801234567", "tollFree"],
      ["+33 9 12 34 56 78", nil, "+33912345678", "voip"],
      ["+33 884 01 23 45", nil, "+33884012345", "sharedCost"],
      ["+33 891 12 34 56", nil, "+33891123456", "premiumRate"],
      ["+33 806 12 34 56", nil, "+33806123456", "uan"],
      ["07400 123456", "GB", "+447400123456", "mobile"],
      ["+44 (0)7400 123456", nil, "+447400123456", "mobile"],
      ["00 1 201-555-0123", "GB", "+12015550123", "fixedLineOrMobile"],
    ].each do |text, region, e164, type|
      number = Phone.parse(text, region)
      refute_nil number, text
      assert_equal e164, number.e164, text
      assert_equal type, number.type, text
    end
  end

  def test_rejects_what_no_plan_accepts
    assert_nil Phone.parse("12", "GB")
    assert_nil Phone.parse("+44 7400 12345")
    assert_nil Phone.parse("+49 1512 3456789")
    assert_nil Phone.parse("07400 123456")
  end

  def test_writes_and_dials
    assert_equal "tel:+447400123456", Phone.to_tel(Phone.parse("+44 7400 123456"))
    assert_equal "0012015550123", Phone.dial_from(Phone.parse("+1 201-555-0123"), "GB")
    assert_equal "011447400123456", Phone.dial_from(Phone.parse("+44 7400 123456"), "US")
    assert_equal "07400123456", Phone.dial_from(Phone.parse("+44 7400 123456"), "GB")
  end
end

What is specific to Ruby

• In Ruby ^ and $ always match at line boundaries: /^\d+$/ accepts "123\nabc". The patterns are anchored with \A and \z.
• match? answers true or false without creating a MatchData, and leaves $~ alone.
• A regular expression literal is compiled once, when the file loads; PLANS and its hashes are frozen.
• exit_code, not exit, for the field: exit is a Kernel method.