Regular Expressions 101

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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

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"\bM10[0-9][0-9]\b" test_str = ("M0\n" "M00\n" "M1\n" "M01\n" "M3\n" "M03\n" "M4\n" "M04\n" "M5\n" "M05\n" "M8\n" "M08\n" "M9\n" "M09\n" "M11\n" "M12\n" "M13\n" "M29\n" "M30\n" "M40\n" "M41\n" "M42\n" "M68\n" "M69\n" "M78\n" "M79\n" "M94\n" "M95\n" "M98\n" "M98 P1111 L10\n" "M99\n" "M100\n" "M101\n" "M102\n" "M103\n" "M104\n" "M105\n" "M106\n" "M107\n" "M108\n" "M109\n" "M110\n" "M111\n" "M112\n" "M113\n" "M114\n" "M115\n" "M116\n" "M117\n" "M118\n" "M119\n" "M120\n" "M121\n" "M122\n" "M123\n" "M124\n" "M125\n" "M126\n" "M127\n" "M128\n" "M129\n" "M130\n" "M131\n" "M132\n" "M133\n" "M134\n" "M135\n" "M136\n" "M137\n" "M138\n" "M139\n" "M140\n" "M141\n" "M142\n" "M143\n" "M144\n" "M145\n" "M146\n" "M147\n" "M148\n" "M149\n" "M150\n" "M151\n" "M152\n" "M153\n" "M154\n" "M155\n" "M156\n" "M157\n" "M158\n" "M159\n" "M160\n" "M161\n" "M162\n" "M163\n" "M164\n" "M165\n" "M166\n" "M167\n" "M168\n" "M169\n" "M170\n" "M171\n" "M172\n" "M173\n" "M174\n" "M175\n" "M176\n" "M177\n" "M178\n" "M179\n" "M180\n" "M181\n" "M182\n" "M183\n" "M184\n" "M185\n" "M186\n" "M187\n" "M188\n" "M189\n" "M190\n" "M191\n" "M192\n" "M193\n" "M194\n" "M195\n" "M196\n" "M197\n" "M198\n" "M199\n" "M200\n" "M201\n" "M202\n" "M203\n" "M204\n" "M205\n" "M206\n" "M207\n" "M208\n" "M209\n" "M210\n" "M211\n" "M212\n" "M213\n" "M214\n" "M215\n" "M216\n" "M217\n" "M218\n" "M219\n" "M220\n" "M221\n" "M222\n" "M223\n" "M224\n" "M225\n" "M226\n" "M227\n" "M228\n" "M229\n" "M230\n" "M231\n" "M232\n" "M233\n" "M234\n" "M235\n" "M236\n" "M237\n" "M238\n" "M239\n" "M240\n" "M241\n" "M242\n" "M243\n" "M244\n" "M245\n" "M246\n" "M247\n" "M248\n" "M249\n" "M250\n" "M251\n" "M252\n" "M253\n" "M254\n" "M255\n" "M256\n" "M257\n" "M258\n" "M259\n" "M260\n" "M261\n" "M262\n" "M263\n" "M264\n" "M265\n" "M266\n" "M267\n" "M268\n" "M269\n" "M270\n" "M271\n" "M272\n" "M273\n" "M274\n" "M275\n" "M276\n" "M277\n" "M278\n" "M279\n" "M280\n" "M281\n" "M282\n" "M283\n" "M284\n" "M285\n" "M286\n" "M287\n" "M288\n" "M289\n" "M290\n" "M291\n" "M292\n" "M293\n" "M294\n" "M295\n" "M296\n" "M297\n" "M298\n" "M299\n" "M300\n" "M301\n" "M302\n" "M303\n" "M304\n" "M305\n" "M306\n" "M307\n" "M308\n" "M309\n" "M310\n" "M311\n" "M312\n" "M313\n" "M314\n" "M315\n" "M316\n" "M317\n" "M318\n" "M319\n" "M320\n" "M321\n" "M322\n" "M323\n" "M324\n" "M325\n" "M326\n" "M327\n" "M328\n" "M329\n" "M330\n" "M331\n" "M332\n" "M333\n" "M334\n" "M335\n" "M336\n" "M337\n" "M338\n" "M339\n" "M340\n" "M341\n" "M342\n" "M343\n" "M344\n" "M345\n" "M346\n" "M347\n" "M348\n" "M349\n" "M350\n" "M351\n" "M352\n" "M353\n" "M354\n" "M355\n" "M356\n" "M357\n" "M358\n" "M359\n" "M360\n" "M361\n" "M362\n" "M363\n" "M364\n" "M365\n" "M366\n" "M367\n" "M368\n" "M369\n" "M370\n" "M371\n" "M372\n" "M373\n" "M374\n" "M375\n" "M376\n" "M377\n" "M378\n" "M379\n" "M380\n" "M381\n" "M382\n" "M383\n" "M384\n" "M385\n" "M386\n" "M387\n" "M388\n" "M389\n" "M390\n" "M391\n" "M392\n" "M393\n" "M394\n" "M395\n" "M396\n" "M397\n" "M398\n" "M399\n" "M400\n" "M401\n" "M402\n" "M403\n" "M404\n" "M405\n" "M406\n" "M407\n" "M408\n" "M409\n" "M410\n" "M411\n" "M412\n" "M413\n" "M414\n" "M415\n" "M416\n" "M417\n" "M418\n" "M419\n" "M420\n" "M421\n" "M422\n" "M423\n" "M424\n" "M425\n" "M426\n" "M427\n" "M428\n" "M429\n" "M430\n" "M431\n" "M432\n" "M433\n" "M434\n" "M435\n" "M436\n" "M437\n" "M438\n" "M439\n" "M440\n" "M441\n" "M442\n" "M443\n" "M444\n" "M445\n" "M446\n" "M447\n" "M448\n" "M449\n" "M450\n" "M451\n" "M452\n" "M453\n" "M454\n" "M455\n" "M456\n" "M457\n" "M458\n" "M459\n" "M460\n" "M461\n" "M462\n" "M463\n" "M464\n" "M465\n" "M466\n" "M467\n" "M468\n" "M469\n" "M470\n" "M471\n" "M472\n" "M473\n" "M474\n" "M475\n" "M476\n" "M477\n" "M478\n" "M479\n" "M480\n" "M481\n" "M482\n" "M483\n" "M484\n" "M485\n" "M486\n" "M487\n" "M488\n" "M489\n" "M490\n" "M491\n" "M492\n" "M493\n" "M494\n" "M495\n" "M496\n" "M497\n" "M498\n" "M499\n" "M500\n" "M501\n" "M502\n" "M503\n" "M504\n" "M505\n" "M506\n" "M507\n" "M508\n" "M509\n" "M510\n" "M511\n" "M512\n" "M513\n" "M514\n" "M515\n" "M516\n" "M517\n" "M518\n" "M519\n" "M520\n" "M521\n" "M522\n" "M523\n" "M524\n" "M525\n" "M526\n" "M527\n" "M528\n" "M529\n" "M530\n" "M531\n" "M532\n" "M533\n" "M534\n" "M535\n" "M536\n" "M537\n" "M538\n" "M539\n" "M540\n" "M541\n" "M542\n" "M543\n" "M544\n" "M545\n" "M546\n" "M547\n" "M548\n" "M549\n" "M550\n" "M551\n" "M552\n" "M553\n" "M554\n" "M555\n" "M556\n" "M557\n" "M558\n" "M559\n" "M560\n" "M561\n" "M562\n" "M563\n" "M564\n" "M565\n" "M566\n" "M567\n" "M568\n" "M569\n" "M570\n" "M571\n" "M572\n" "M573\n" "M574\n" "M575\n" "M576\n" "M577\n" "M578\n" "M579\n" "M580\n" "M581\n" "M582\n" "M583\n" "M584\n" "M585\n" "M586\n" "M587\n" "M588\n" "M589\n" "M590\n" "M591\n" "M592\n" "M593\n" "M594\n" "M595\n" "M596\n" "M597\n" "M598\n" "M599\n" "M600\n" "M601\n" "M602\n" "M603\n" "M604\n" "M605\n" "M606\n" "M607\n" "M608\n" "M609\n" "M610\n" "M611\n" "M612\n" "M613\n" "M614\n" "M615\n" "M616\n" "M617\n" "M618\n" "M619\n" "M620\n" "M621\n" "M622\n" "M623\n" "M624\n" "M625\n" "M626\n" "M627\n" "M628\n" "M629\n" "M630\n" "M631\n" "M632\n" "M633\n" "M634\n" "M635\n" "M636\n" "M637\n" "M638\n" "M639\n" "M640\n" "M641\n" "M642\n" "M643\n" "M644\n" "M645\n" "M646\n" "M647\n" "M648\n" "M649\n" "M650\n" "M651\n" "M652\n" "M653\n" "M654\n" "M655\n" "M656\n" "M657\n" "M658\n" "M659\n" "M660\n" "M661\n" "M662\n" "M663\n" "M664\n" "M665\n" "M666\n" "M667\n" "M668\n" "M669\n" "M670\n" "M671\n" "M672\n" "M673\n" "M674\n" "M675\n" "M676\n" "M677\n" "M678\n" "M679\n" "M680\n" "M681\n" "M682\n" "M683\n" "M684\n" "M685\n" "M686\n" "M687\n" "M688\n" "M689\n" "M690\n" "M691\n" "M692\n" "M693\n" "M694\n" "M695\n" "M696\n" "M697\n" "M698\n" "M699\n" "M700\n" "M701\n" "M702\n" "M703\n" "M704\n" "M705\n" "M706\n" "M707\n" "M708\n" "M709\n" "M710\n" "M711\n" "M712\n" "M713\n" "M714\n" "M715\n" "M716\n" "M717\n" "M718\n" "M719\n" "M720\n" "M721\n" "M722\n" "M723\n" "M724\n" "M725\n" "M726\n" "M727\n" "M728\n" "M729\n" "M730\n" "M731\n" "M732\n" "M733\n" "M734\n" "M735\n" "M736\n" "M737\n" "M738\n" "M739\n" "M740\n" "M741\n" "M742\n" "M743\n" "M744\n" "M745\n" "M746\n" "M747\n" "M748\n" "M749\n" "M750\n" "M751\n" "M752\n" "M753\n" "M754\n" "M755\n" "M756\n" "M757\n" "M758\n" "M759\n" "M760\n" "M761\n" "M762\n" "M763\n" "M764\n" "M765\n" "M766\n" "M767\n" "M768\n" "M769\n" "M770\n" "M771\n" "M772\n" "M773\n" "M774\n" "M775\n" "M776\n" "M777\n" "M778\n" "M779\n" "M780\n" "M781\n" "M782\n" "M783\n" "M784\n" "M785\n" "M786\n" "M787\n" "M788\n" "M789\n" "M790\n" "M791\n" "M792\n" "M793\n" "M794\n" "M795\n" "M796\n" "M797\n" "M798\n" "M799\n" "M800\n" "M801\n" "M802\n" "M803\n" "M804\n" "M805\n" "M806\n" "M807\n" "M808\n" "M809\n" "M810\n" "M811\n" "M812\n" "M813\n" "M814\n" "M815\n" "M816\n" "M817\n" "M818\n" "M819\n" "M820\n" "M821\n" "M822\n" "M823\n" "M824\n" "M825\n" "M826\n" "M827\n" "M828\n" "M829\n" "M830\n" "M831\n" "M832\n" "M833\n" "M834\n" "M835\n" "M836\n" "M837\n" "M838\n" "M839\n" "M840\n" "M841\n" "M842\n" "M843\n" "M844\n" "M845\n" "M846\n" "M847\n" "M848\n" "M849\n" "M850\n" "M851\n" "M852\n" "M853\n" "M854\n" "M855\n" "M856\n" "M857\n" "M858\n" "M859\n" "M860\n" "M861\n" "M862\n" "M863\n" "M864\n" "M865\n" "M866\n" "M867\n" "M868\n" "M869\n" "M870\n" "M871\n" "M872\n" "M873\n" "M874\n" "M875\n" "M876\n" "M877\n" "M878\n" "M879\n" "M880\n" "M881\n" "M882\n" "M883\n" "M884\n" "M885\n" "M886\n" "M887\n" "M888\n" "M889\n" "M890\n" "M891\n" "M892\n" "M893\n" "M894\n" "M895\n" "M896\n" "M897\n" "M898\n" "M899\n" "M900\n" "M901\n" "M902\n" "M903\n" "M904\n" "M905\n" "M906\n" "M907\n" "M908\n" "M909\n" "M910\n" "M911\n" "M912\n" "M913\n" "M914\n" "M915\n" "M916\n" "M917\n" "M918\n" "M919\n" "M920\n" "M921\n" "M922\n" "M923\n" "M924\n" "M925\n" "M926\n" "M927\n" "M928\n" "M929\n" "M930\n" "M931\n" "M932\n" "M933\n" "M934\n" "M935\n" "M936\n" "M937\n" "M938\n" "M939\n" "M940\n" "M941\n" "M942\n" "M943\n" "M944\n" "M945\n" "M946\n" "M947\n" "M948\n" "M949\n" "M950\n" "M951\n" "M952\n" "M953\n" "M954\n" "M955\n" "M956\n" "M957\n" "M958\n" "M959\n" "M960\n" "M961\n" "M962\n" "M963\n" "M964\n" "M965\n" "M966\n" "M967\n" "M968\n" "M969\n" "M970\n" "M971\n" "M972\n" "M973\n" "M974\n" "M975\n" "M976\n" "M977\n" "M978\n" "M979\n" "M980\n" "M981\n" "M982\n" "M983\n" "M984\n" "M985\n" "M986\n" "M987\n" "M988\n" "M989\n" "M990\n" "M991\n" "M992\n" "M993\n" "M994\n" "M995\n" "M996\n" "M997\n" "M998\n" "M999\n" "M1000\n" "M1001\n" "M1002\n" "M1003\n" "M1004\n" "M1005\n" "M1006\n" "M1007\n" "M1008\n" "M1009\n" "M1010\n" "M1011\n" "M1012\n" "M1013\n" "M1014\n" "M1015\n" "M1016\n" "M1017\n" "M1018\n" "M1019\n" "M1020\n" "M1021\n" "M1022\n" "M1023\n" "M1024\n" "M1025\n" "M1026\n" "M1027\n" "M1028\n" "M1029\n" "M1030\n" "M1031\n" "M1032\n" "M1033\n" "M1034\n" "M1035\n" "M1036\n" "M1037\n" "M1038\n" "M1039\n" "M1040\n" "M1041\n" "M1042\n" "M1043\n" "M1044\n" "M1045\n" "M1046\n" "M1047\n" "M1048\n" "M1049\n" "M1050\n" "M1051\n" "M1052\n" "M1053\n" "M1054\n" "M1055\n" "M1056\n" "M1057\n" "M1058\n" "M1059\n" "M1060\n" "M1061\n" "M1062\n" "M1063\n" "M1064\n" "M1065\n" "M1066\n" "M1067\n" "M1068\n" "M1069\n" "M1070\n" "M1071\n" "M1072\n" "M1073\n" "M1074\n" "M1075\n" "M1076\n" "M1077\n" "M1078\n" "M1079\n" "M1080\n" "M1081\n" "M1082\n" "M1083\n" "M1084\n" "M1085\n" "M1086\n" "M1087\n" "M1088\n" "M1089\n" "M1090\n" "M1091\n" "M1092\n" "M1093\n" "M1094\n" "M1095\n" "M1096\n" "M1097\n" "M1098\n" "M1099\n" "M1100\n" "M1101\n\n") matches = re.finditer(regex, test_str, re.MULTILINE) for matchNum, match in enumerate(matches, start=1): print ("Match {matchNum} was found at {start}-{end}: {match}".format(matchNum = matchNum, start = match.start(), end = match.end(), match = match.group())) for groupNum in range(0, len(match.groups())): groupNum = groupNum + 1 print ("Group {groupNum} found at {start}-{end}: {group}".format(groupNum = groupNum, start = match.start(groupNum), end = match.end(groupNum), group = match.group(groupNum))) # 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