Regular Expressions 101

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An explanation of your regex will be automatically generated as you type.
Detailed match information will be displayed here automatically.
  • All Tokens
  • Common Tokens
  • General Tokens
  • Anchors
  • Meta Sequences
  • Quantifiers
  • Group Constructs
  • Character Classes
  • Flags/Modifiers
  • Substitution
  • A single character of: a, b or c
    [abc]
  • A character except: a, b or c
    [^abc]
  • A character in the range: a-z
    [a-z]
  • A character not in the range: a-z
    [^a-z]
  • A character in the range: a-z or A-Z
    [a-zA-Z]
  • Any single character
    .
  • Alternate - match either a or b
    a|b
  • Any whitespace character
    \s
  • Any non-whitespace character
    \S
  • Any digit
    \d
  • Any non-digit
    \D
  • Any word character
    \w
  • Any non-word character
    \W
  • Non-capturing group
    (?:...)
  • Capturing group
    (...)
  • Zero or one of a
    a?
  • Zero or more of a
    a*
  • One or more of a
    a+
  • Exactly 3 of a
    a{3}
  • 3 or more of a
    a{3,}
  • Between 3 and 6 of a
    a{3,6}
  • Start of string
    ^
  • End of string
    $
  • A word boundary
    \b
  • Non-word boundary
    \B

Regular Expression
No Match

/
/
gm

Test String

Substitution

Processing...

Code Generator

Language

Generated Code

# coding=utf8 # the above tag defines encoding for this document and is for Python 2.x compatibility import re regex = r"^(.+?)\t([-\d, ]+)\t(.+?) .+$" test_str = ("Afghanistan 93 AF / AFG 29.121.286 647.500 20.65 Billion\n" "Albania 355 AL / ALB 2.986.952 28.748 12.8 Billion\n" "Algeria 213 DZ / DZA 34.586.184 2.381.740 215.7 Billion\n" "American Samoa 1-684 AS / ASM 57.881 199 462.2 Million\n" "Andorra 376 AD / AND 84.000 468 4.8 Billion\n" "Angola 244 AO / AGO 13.068.161 1.246.700 124 Billion\n" "Anguilla 1-264 AI / AIA 13.254 102 175.4 Million\n" "Antarctica 672 AQ / ATA 0 14.000.000 \n" "Antigua and Barbuda 1-268 AG / ATG 86.754 443 1.22 Billion\n" "Argentina 54 AR / ARG 41.343.201 2.766.890 484.6 Billion\n" "Armenia 374 AM / ARM 2.968.000 29.800 10.44 Billion\n" "Aruba 297 AW / ABW 71.566 193 2.516 Billion\n" "Australia 61 AU / AUS 21.515.754 7.686.850 1.488 Trillion\n" "Austria 43 AT / AUT 8.205.000 83.858 417.9 Billion\n" "Azerbaijan 994 AZ / AZE 8.303.512 86.600 76.01 Billion\n" "Bahamas 1-242 BS / BHS 301.790 13.940 8.373 Billion\n" "Bahrain 973 BH / BHR 738.004 665 28.36 Billion\n" "Bangladesh 880 BD / BGD 156.118.464 144.000 140.2 Billion\n" "Barbados 1-246 BB / BRB 285.653 431 4.262 Billion\n" "Belarus 375 BY / BLR 9.685.000 207.600 69.24 Billion\n" "Belgium 32 BE / BEL 10.403.000 30.510 507.4 Billion\n" "Belize 501 BZ / BLZ 314.522 22.966 1.637 Billion\n" "Benin 229 BJ / BEN 9.056.010 112.620 8.359 Billion\n" "Bermuda 1-441 BM / BMU 65.365 53 5.6 Billion\n" "Bhutan 975 BT / BTN 699.847 47.000 2.133 Billion\n" "Bolivia 591 BO / BOL 9.947.418 1.098.580 30.79 Billion\n" "Bosnia and Herzegovina 387 BA / BIH 4.590.000 51.129 18.87 Billion\n" "Botswana 267 BW / BWA 2.029.307 600.370 15.53 Billion\n" "Brazil 55 BR / BRA 201.103.330 8.511.965 2.19 Trillion\n" "British Indian Ocean Territory 246 IO / IOT 4.000 60 \n" "British Virgin Islands 1-284 VG / VGB 21.730 153 1.095 Billion\n" "Brunei 673 BN / BRN 395.027 5.770 16.56 Billion\n" "Bulgaria 359 BG / BGR 7.148.785 110.910 53.7 Billion\n" "Burkina Faso 226 BF / BFA 16.241.811 274.200 12.13 Billion\n" "Burundi 257 BI / BDI 9.863.117 27.830 2.676 Billion\n" "Cambodia 855 KH / KHM 14.453.680 181.040 15.64 Billion\n" "Cameroon 237 CM / CMR 19.294.149 475.440 27.88 Billion\n" "Canada 1 CA / CAN 33.679.000 9.984.670 1.825 Trillion\n" "Cape Verde 238 CV / CPV 508.659 4.033 1.955 Billion\n" "Cayman Islands 1-345 KY / CYM 44.270 262 2.25 Billion\n" "Central African Republic 236 CF / CAF 4.844.927 622.984 2.05 Billion\n" "Chad 235 TD / TCD 10.543.464 1.284.000 13.59 Billion\n" "Chile 56 CL / CHL 16.746.491 756.950 281.7 Billion\n" "China 86 CN / CHN 1.330.044.000 9.596.960 9.33 Trillion\n" "Christmas Island 61 CX / CXR 1.500 135 \n" "Cocos Islands 61 CC / CCK 628 14 \n" "Colombia 57 CO / COL 47.790.000 1.138.910 369.2 Billion\n" "Comoros 269 KM / COM 773.407 2.170 658 Million\n" "Cook Islands 682 CK / COK 21.388 240 183.2 Million\n" "Costa Rica 506 CR / CRI 4.516.220 51.100 48.51 Billion\n" "Croatia 385 HR / HRV 4.491.000 56.542 59.14 Billion\n" "Cuba 53 CU / CUB 11.423.000 110.860 72.3 Billion\n" "Curacao 599 CW / CUW 141.766 444 5.6 Billion\n" "Cyprus 357 CY / CYP 1.102.677 9.250 21.78 Billion\n" "Czech Republic 420 CZ / CZE 10.476.000 78.866 194.8 Billion\n" "Democratic Republic of the Congo 243 CD / COD 70.916.439 2.345.410 18.56 Billion\n" "Denmark 45 DK / DNK 5.484.000 43.094 324.3 Billion\n" "Djibouti 253 DJ / DJI 740.528 23.000 1.459 Billion\n" "Dominica 1-767 DM / DMA 72.813 754 495 Million\n" "Dominican Republic 1-809, 1-829, 1-849 DO / DOM 9.823.821 48.730 59.27 Billion\n" "East Timor 670 TL / TLS 1.154.625 15.007 6.129 Billion\n" "Ecuador 593 EC / ECU 14.790.608 283.560 91.41 Billion\n" "Egypt 20 EG / EGY 80.471.869 1.001.450 262 Billion\n" "El Salvador 503 SV / SLV 6.052.064 21.040 24.67 Billion\n" "Equatorial Guinea 240 GQ / GNQ 1.014.999 28.051 17.08 Billion\n" "Eritrea 291 ER / ERI 5.792.984 121.320 3.438 Billion\n" "Estonia 372 EE / EST 1.291.170 45.226 24.28 Billion\n" "Ethiopia 251 ET / ETH 88.013.491 1.127.127 47.34 Billion\n" "Falkland Islands 500 FK / FLK 2.638 12.173 164.5 Million\n" "Faroe Islands 298 FO / FRO 48.228 1.399 2.32 Billion\n" "Fiji 679 FJ / FJI 875.983 18.270 4.218 Billion\n" "Finland 358 FI / FIN 5.244.000 337.030 259.6 Billion\n" "France 33 FR / FRA 64.768.389 547.030 2.739 Trillion\n" "French Polynesia 689 PF / PYF 270.485 4.167 5.65 Billion\n" "Gabon 241 GA / GAB 1.545.255 267.667 19.97 Billion\n" "Gambia 220 GM / GMB 1.593.256 11.300 896 Million\n" "Georgia 995 GE / GEO 4.630.000 69.700 15.95 Billion\n" "Germany 49 DE / DEU 81.802.257 357.021 3.593 Trillion\n" "Ghana 233 GH / GHA 24.339.838 239.460 45.55 Billion\n" "Gibraltar 350 GI / GIB 27.884 7 1.106 Billion\n" "Greece 30 GR / GRC 11.000.000 131.940 243.3 Billion\n" "Greenland 299 GL / GRL 56.375 2.166.086 2.16 Billion\n" "Grenada 1-473 GD / GRD 107.818 344 811 Million\n" "Guam 1-671 GU / GUM 159.358 549 4.6 Billion\n" "Guatemala 502 GT / GTM 13.550.440 108.890 53.9 Billion\n" "Guernsey 44-1481 GG / GGY 65.228 78 2.742 Billion\n" "Guinea 224 GN / GIN 10.324.025 245.857 6.544 Billion\n" "Guinea-Bissau 245 GW / GNB 1.565.126 36.120 880 Million\n" "Guyana 592 GY / GUY 748.486 214.970 3.02 Billion\n" "Haiti 509 HT / HTI 9.648.924 27.750 8.287 Billion\n" "Honduras 504 HN / HND 7.989.415 112.090 18.88 Billion\n" "Hong Kong 852 HK / HKG 6.898.686 1.092 272.1 Billion\n" "Hungary 36 HU / HUN 9.982.000 93.030 130.6 Billion\n" "Iceland 354 IS / ISL 308.910 103.000 14.59 Billion\n" "India 91 IN / IND 1.173.108.018 3.287.590 1.67 Trillion\n" "Indonesia 62 ID / IDN 242.968.342 1.919.440 867.5 Billion\n" "Iran 98 IR / IRN 76.923.300 1.648.000 411.9 Billion\n" "Iraq 964 IQ / IRQ 29.671.605 437.072 221.8 Billion\n" "Ireland 353 IE / IRL 4.622.917 70.280 220.9 Billion\n" "Isle of Man 44-1624 IM / IMN 75.049 572 4.076 Billion\n" "Israel 972 IL / ISR 7.353.985 20.770 272.7 Billion\n" "Italy 39 IT / ITA 60.340.328 301.230 2.068 Trillion\n" "Ivory Coast 225 CI / CIV 21.058.798 322.460 28.28 Billion\n" "Jamaica 1-876 JM / JAM 2.847.232 10.991 14.39 Billion\n" "Japan 81 JP / JPN 127.288.000 377.835 5.007 Trillion\n" "Jersey 44-1534 JE / JEY 90.812 116 5.1 Billion\n" "Jordan 962 JO / JOR 6.407.085 92.300 34.08 Billion\n" "Kazakhstan 7 KZ / KAZ 15.340.000 2.717.300 224.9 Billion\n" "Kenya 254 KE / KEN 40.046.566 582.650 45.31 Billion\n" "Kiribati 686 KI / KIR 92.533 811 173 Million\n" "Kosovo 383 XK / XKX 1.800.000 10.887 7.15 Billion\n" "Kuwait 965 KW / KWT 2.789.132 17.820 179.5 Billion\n" "Kyrgyzstan 996 KG / KGZ 5.508.626 198.500 7.234 Billion\n" "Laos 856 LA / LAO 6.368.162 236.800 10.1 Billion\n" "Latvia 371 LV / LVA 2.217.969 64.589 30.38 Billion\n" "Lebanon 961 LB / LBN 4.125.247 10.400 43.49 Billion\n" "Lesotho 266 LS / LSO 1.919.552 30.355 2.457 Billion\n" "Liberia 231 LR / LBR 3.685.076 111.370 1.977 Billion\n" "Libya 218 LY / LBY 6.461.454 1.759.540 70.92 Billion\n" "Liechtenstein 423 LI / LIE 35.000 160 5.113 Billion\n" "Lithuania 370 LT / LTU 2.944.459 65.200 46.71 Billion\n" "Luxembourg 352 LU / LUX 497.538 2.586 60.54 Billion\n" "Macao 853 MO / MAC 449.198 254 51.68 Billion\n" "Macedonia 389 MK / MKD 2.062.294 25.333 10.65 Billion\n" "Madagascar 261 MG / MDG 21.281.844 587.040 10.53 Billion\n" "Malawi 265 MW / MWI 15.447.500 118.480 3.683 Billion\n" "Malaysia 60 MY / MYS 28.274.729 329.750 312.4 Billion\n" "Maldives 960 MV / MDV 395.650 300 2.27 Billion\n" "Mali 223 ML / MLI 13.796.354 1.240.000 11.37 Billion\n" "Malta 356 MT / MLT 403.000 316 9.541 Billion\n" "Marshall Islands 692 MH / MHL 65.859 181 193 Million\n" "Mauritania 222 MR / MRT 3.205.060 1.030.700 4.183 Billion\n" "Mauritius 230 MU / MUS 1.294.104 2.040 11.9 Billion\n" "Mayotte 262 YT / MYT 159.042 374 \n" "Mexico 52 MX / MEX 112.468.855 1.972.550 1.327 Trillion\n" "Micronesia 691 FM / FSM 107.708 702 339 Million\n" "Moldova 373 MD / MDA 4.324.000 33.843 7.932 Billion\n" "Monaco 377 MC / MCO 32.965 2 5.748 Billion\n" "Mongolia 976 MN / MNG 3.086.918 1.565.000 11.14 Billion\n" "Montenegro 382 ME / MNE 666.730 14.026 4.518 Billion\n" "Montserrat 1-664 MS / MSR 9.341 102 \n" "Morocco 212 MA / MAR 31.627.428 446.550 104.8 Billion\n" "Mozambique 258 MZ / MOZ 22.061.451 801.590 14.67 Billion\n" "Myanmar 95 MM / MMR 53.414.374 678.500 59.43 Billion\n" "Namibia 264 NA / NAM 2.128.471 825.418 12.3 Billion\n" "Nauru 674 NR / NRU 10.065 21 \n" "Nepal 977 NP / NPL 28.951.852 140.800 19.34 Billion\n" "Netherlands 31 NL / NLD 16.645.000 41.526 722.3 Billion\n" "Netherlands Antilles 599 AN / ANT 136.197 960 \n" "New Caledonia 687 NC / NCL 216.494 19.060 9.28 Billion\n" "New Zealand 64 NZ / NZL 4.252.277 268.680 181.1 Billion\n" "Nicaragua 505 NI / NIC 5.995.928 129.494 11.26 Billion\n" "Niger 227 NE / NER 15.878.271 1.267.000 7.304 Billion\n" "Nigeria 234 NG / NGA 154.000.000 923.768 502 Billion\n" "Niue 683 NU / NIU 2.166 260 10.01 Million\n" "North Korea 850 KP / PRK 22.912.177 120.540 28 Billion\n" "Northern Mariana Islands 1-670 MP / MNP 53.883 477 733 Million\n" "Norway 47 NO / NOR 5.009.150 324.220 515.8 Billion\n" "Oman 968 OM / OMN 2.967.717 212.460 81.95 Billion\n" "Pakistan 92 PK / PAK 184.404.791 803.940 236.5 Billion\n" "Palau 680 PW / PLW 19.907 458 221 Million\n" "Palestine 970 PS / PSE 3.800.000 5.970 6.641 Billion\n" "Panama 507 PA / PAN 3.410.676 78.200 40.62 Billion\n" "Papua New Guinea 675 PG / PNG 6.064.515 462.840 16.1 Billion\n" "Paraguay 595 PY / PRY 6.375.830 406.750 30.56 Billion\n" "Peru 51 PE / PER 29.907.003 1.285.220 210.3 Billion\n" "Philippines 63 PH / PHL 99.900.177 300.000 272.2 Billion\n" "Pitcairn 64 PN / PCN 46 47 \n" "Poland 48 PL / POL 38.500.000 312.685 513.9 Billion\n" "Portugal 351 PT / PRT 10.676.000 92.391 219.3 Billion\n" "Puerto Rico 1-787, 1-939 PR / PRI 3.916.632 9.104 93.52 Billion\n" "Qatar 974 QA / QAT 840.926 11.437 213.1 Billion\n" "Republic of the Congo 242 CG / COG 3.039.126 342.000 14.25 Billion\n" "Reunion 262 RE / REU 776.948 2.517 \n" "Romania 40 RO / ROU 21.959.278 237.500 188.9 Billion\n" "Russia 7 RU / RUS 140.702.000 17.100.000 2.113 Trillion\n" "Rwanda 250 RW / RWA 11.055.976 26.338 7.7 Billion\n" "Saint Barthelemy 590 BL / BLM 8.450 21 \n" "Saint Helena 290 SH / SHN 7.460 410 \n" "Saint Kitts and Nevis 1-869 KN / KNA 51.134 261 767 Million\n" "Saint Lucia 1-758 LC / LCA 160.922 616 1.377 Billion\n" "Saint Martin 590 MF / MAF 35.925 53 561.5 Million\n" "Saint Pierre and Miquelon 508 PM / SPM 7.012 242 215.3 Million\n" "Saint Vincent and the Grenadines 1-784 VC / VCT 104.217 389 742 Million\n" "Samoa 685 WS / WSM 192.001 2.944 705 Million\n" "San Marino 378 SM / SMR 31.477 61 1.866 Billion\n" "Sao Tome and Principe 239 ST / STP 175.808 1.001 311 Million\n" "Saudi Arabia 966 SA / SAU 25.731.776 1.960.582 718.5 Billion\n" "Senegal 221 SN / SEN 12.323.252 196.190 15.36 Billion\n" "Serbia 381 RS / SRB 7.344.847 88.361 43.68 Billion\n" "Seychelles 248 SC / SYC 88.340 455 1.271 Billion\n" "Sierra Leone 232 SL / SLE 5.245.695 71.740 4.607 Billion\n" "Singapore 65 SG / SGP 4.701.069 693 295.7 Billion\n" "Sint Maarten 1-721 SX / SXM 37.429 34 794.7 Million\n" "Slovakia 421 SK / SVK 5.455.000 48.845 96.96 Billion\n" "Slovenia 386 SI / SVN 2.007.000 20.273 46.82 Billion\n" "Solomon Islands 677 SB / SLB 559.198 28.450 1.099 Billion\n" "Somalia 252 SO / SOM 10.112.453 637.657 2.372 Billion\n" "South Africa 27 ZA / ZAF 49.000.000 1.219.912 353.9 Billion\n" "South Korea 82 KR / KOR 48.422.644 98.480 1.198 Trillion\n" "South Sudan 211 SS / SSD 8.260.490 644.329 11.77 Billion\n" "Spain 34 ES / ESP 46.505.963 504.782 1.356 Trillion\n" "Sri Lanka 94 LK / LKA 21.513.990 65.610 65.12 Billion\n" "Sudan 249 SD / SDN 35.000.000 1.861.484 52.5 Billion\n" "Suriname 597 SR / SUR 492.829 163.270 5.009 Billion\n" "Svalbard and Jan Mayen 47 SJ / SJM 2.550 62.049 \n" "Swaziland 268 SZ / SWZ 1.354.051 17.363 3.807 Billion\n" "Sweden 46 SE / SWE 9.555.893 449.964 552 Billion\n" "Switzerland 41 CH / CHE 7.581.000 41.290 646.2 Billion\n" "Syria 963 SY / SYR 22.198.110 185.180 64.7 Billion\n" "Taiwan 886 TW / TWN 22.894.384 35.980 484.7 Billion\n" "Tajikistan 992 TJ / TJK 7.487.489 143.100 8.513 Billion\n" "Tanzania 255 TZ / TZA 41.892.895 945.087 31.94 Billion\n" "Thailand 66 TH / THA 67.089.500 514.000 400.9 Billion\n" "Togo 228 TG / TGO 6.587.239 56.785 4.299 Billion\n" "Tokelau 690 TK / TKL 1.466 10 \n" "Tonga 676 TO / TON 122.580 748 477 Million\n" "Trinidad and Tobago 1-868 TT / TTO 1.228.691 5.128 27.13 Billion\n" "Tunisia 216 TN / TUN 10.589.025 163.610 48.38 Billion\n" "Turkey 90 TR / TUR 77.804.122 780.580 821.8 Billion\n" "Turkmenistan 993 TM / TKM 4.940.916 488.100 40.56 Billion\n" "Turks and Caicos Islands 1-649 TC / TCA 20.556 430 \n" "Tuvalu 688 TV / TUV 10.472 26 38 Million\n" "U.S. Virgin Islands 1-340 VI / VIR 108.708 352 \n" "Uganda 256 UG / UGA 33.398.682 236.040 22.6 Billion\n" "Ukraine 380 UA / UKR 45.415.596 603.700 175.5 Billion\n" "United Arab Emirates 971 AE / ARE 4.975.593 82.880 390 Billion\n" "United Kingdom 44 GB / GBR 62.348.447 244.820 2.49 Trillion\n" "United States 1 US / USA 310.232.863 9.629.091 16.72 Trillion\n" "Uruguay 598 UY / URY 3.477.000 176.220 57.11 Billion\n" "Uzbekistan 998 UZ / UZB 27.865.738 447.400 55.18 Billion\n" "Vanuatu 678 VU / VUT 221.552 12.200 828 Million\n" "Vatican 379 VA / VAT 921 0 \n" "Venezuela 58 VE / VEN 27.223.228 912.050 367.5 Billion\n" "Vietnam 84 VN / VNM 89.571.130 329.560 170 Billion\n" "Wallis and Futuna 681 WF / WLF 16.025 274 \n" "Western Sahara 212 EH / ESH 273.008 266.000 \n" "Yemen 967 YE / YEM 23.495.361 527.970 43.89 Billion\n" "Zambia 260 ZM / ZMB 13.460.305 752.614 22.24 Billion\n" "Zimbabwe 263 ZW / ZWE 11.651.858 390.580 10.48 Billion\n") subst = "\\3\\t\\2\\t\\1" # You can manually specify the number of replacements by changing the 4th argument result = re.sub(regex, subst, test_str, 0, re.MULTILINE) if result: print (result) # Note: for Python 2.7 compatibility, use ur"" to prefix the regex and u"" to prefix the test string and substitution.

Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for Python, please visit: https://docs.python.org/3/library/re.html