diff --git a/README.md b/README.md
index 13420b29f..816dc09a9 100644
--- a/README.md
+++ b/README.md
@@ -1 +1,35 @@
-# javascript-calculator-precourse
\ No newline at end of file
+
+## **문자열 덧셈 계산기**
+
+### **📘기능 요구 사항**
+
+입력한 문자열에서 숫자를 추출하여 더하는 계산기를 구현한다.
+
+- 쉼표(,) 또는 콜론(:)을 구분자로 가지는 문자열을 전달하는 경우 구분자를 기준으로 분리한 각 숫자의 합을 반환한다.
+    ◦ 예: "" => 0, "1,2" => 3, "1,2,3" => 6, "1,2:3" => 6
+- 앞의 기본 구분자(쉼표, 콜론) 외에 커스텀 구분자를 지정할 수 있다. 커스텀 구분자는 문자열 앞부분의 "//"와 "\n" 사이에 위치하는 문자를 커스텀 구분자로 사용한다.
+    - 예를 들어 "//;\n1;2;3"과 같이 값을 입력할 경우 커스텀 구분자는 세미콜론(;)이며, 결과 값은 6이 반환되어야 한다.
+- 사용자가 잘못된 값을 입력할 경우 "[ERROR]"로 시작하는 메시지와 함께 `Error`를 발생시킨 후 애플리케이션은 종료되어야 한다.
+
+### **입출력 요구 사항**
+
+**입력**
+
+- 구분자와 양수로 구성된 문자열
+
+**출력**
+
+- 덧셈 결과
+    
+    ```
+    결과 : 6
+    ```
+
+## 💡생각해보기
+1. 문자열을 입력받는다.
+2. ,과 :을 기본 구분자로 넣는다.
+3. 받은 문자열을 검사한다.
+    3-1. 커스텀 문자열이라면 //와\n사이에 위치한 문자를 커스텀 구분자로 사용한다.
+    3-2. 아니라면 기존 구분자를 사용해서 문자열을 계산한다.
+    3-3. 잘못된 문자열이 입력되면 "[ERROR]"로 시작하는 메시지와 함께 `Error`를 발생 시키고 종료한다.
+4. 문자열 수들의 합을 구해서 "결과: 결과 값" 형식으로 출력한다.
\ No newline at end of file
diff --git a/__tests__/ApplicationTest.js b/__tests__/ApplicationTest.js
index 7c6962dd1..24cd04003 100644
--- a/__tests__/ApplicationTest.js
+++ b/__tests__/ApplicationTest.js
@@ -1,6 +1,7 @@
 import App from "../src/App.js";
 import { MissionUtils } from "@woowacourse/mission-utils";
 
+
 const mockQuestions = (inputs) => {
   MissionUtils.Console.readLineAsync = jest.fn();
 
diff --git a/package-lock.json b/package-lock.json
index 2edacf7e3..6c5e8e06a 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -8,13 +8,14 @@
       "name": "javascript-calculator",
       "version": "0.0.0",
       "dependencies": {
-        "@woowacourse/mission-utils": "^2.2.0"
+        "prompt": "^1.3.0"
       },
       "devDependencies": {
         "@babel/core": "^7.25.8",
         "@babel/preset-env": "^7.25.8",
+        "@woowacourse/mission-utils": "^2.2.0",
         "babel-jest": "^29.6.0",
-        "jest": "^29.6.0"
+        "jest": "^29.7.0"
       },
       "engines": {
         "node": ">=20.17.0",
@@ -1790,6 +1791,15 @@
       "dev": true,
       "license": "MIT"
     },
+    "node_modules/@colors/colors": {
+      "version": "1.5.0",
+      "resolved": "https://registry.npmjs.org/@colors/colors/-/colors-1.5.0.tgz",
+      "integrity": "sha512-ooWCrlZP11i8GImSjTHYHLkvFDP48nS4+204nGb1RiX/WXYHmJA2III9/e2DWVabCESdW7hBAEzHRqUn9OUVvQ==",
+      "license": "MIT",
+      "engines": {
+        "node": ">=0.1.90"
+      }
+    },
     "node_modules/@istanbuljs/load-nyc-config": {
       "version": "1.1.0",
       "resolved": "https://registry.npmjs.org/@istanbuljs/load-nyc-config/-/load-nyc-config-1.1.0.tgz",
@@ -2719,6 +2729,7 @@
       "version": "2.2.0",
       "resolved": "https://registry.npmjs.org/@woowacourse/mission-utils/-/mission-utils-2.2.0.tgz",
       "integrity": "sha512-yuG68cd42EsvI43c/7T6eQOKgobRkMGqvpN9gp4P134L1LQ/BksA+4hfDt8Qc71TzQEf3cb17y2L7BWwXudu8Q==",
+      "dev": true,
       "engines": {
         "node": ">=20.17.0",
         "npm": ">=10.8.2"
@@ -2787,6 +2798,12 @@
         "sprintf-js": "~1.0.2"
       }
     },
+    "node_modules/async": {
+      "version": "3.2.3",
+      "resolved": "https://registry.npmjs.org/async/-/async-3.2.3.tgz",
+      "integrity": "sha512-spZRyzKL5l5BZQrr/6m/SqFdBN0q3OCI0f9rjfBzCMBIP4p75P620rR3gTmaksNOhmzgdxcaxdNfMy6anrbM0g==",
+      "license": "MIT"
+    },
     "node_modules/babel-jest": {
       "version": "29.7.0",
       "resolved": "https://registry.npmjs.org/babel-jest/-/babel-jest-29.7.0.tgz",
@@ -3224,6 +3241,15 @@
       "dev": true,
       "license": "MIT"
     },
+    "node_modules/colors": {
+      "version": "1.0.3",
+      "resolved": "https://registry.npmjs.org/colors/-/colors-1.0.3.tgz",
+      "integrity": "sha512-pFGrxThWcWQ2MsAz6RtgeWe4NK2kUE1WfsrvvlctdII745EW9I0yflqhe7++M5LEc7bV2c/9/5zc8sFcpL0Drw==",
+      "license": "MIT",
+      "engines": {
+        "node": ">=0.1.90"
+      }
+    },
     "node_modules/concat-map": {
       "version": "0.0.1",
       "resolved": "https://registry.npmjs.org/concat-map/-/concat-map-0.0.1.tgz",
@@ -3365,6 +3391,14 @@
         "node": ">= 8"
       }
     },
+    "node_modules/cycle": {
+      "version": "1.0.3",
+      "resolved": "https://registry.npmjs.org/cycle/-/cycle-1.0.3.tgz",
+      "integrity": "sha512-TVF6svNzeQCOpjCqsy0/CSy8VgObG3wXusJ73xW2GbG5rGx7lC8zxDSURicsXI2UsGdi2L0QNRCi745/wUDvsA==",
+      "engines": {
+        "node": ">=0.4.0"
+      }
+    },
     "node_modules/debug": {
       "version": "4.3.7",
       "resolved": "https://registry.npmjs.org/debug/-/debug-4.3.7.tgz",
@@ -3559,6 +3593,14 @@
         "node": "^14.15.0 || ^16.10.0 || >=18.0.0"
       }
     },
+    "node_modules/eyes": {
+      "version": "0.1.8",
+      "resolved": "https://registry.npmjs.org/eyes/-/eyes-0.1.8.tgz",
+      "integrity": "sha512-GipyPsXO1anza0AOZdy69Im7hGFCNB7Y/NGjDlZGJ3GJJLtwNSb2vrzYrTYJRrRloVx7pl+bhUaTB8yiccPvFQ==",
+      "engines": {
+        "node": "> 0.1.90"
+      }
+    },
     "node_modules/fast-json-stable-stringify": {
       "version": "2.1.0",
       "resolved": "https://registry.npmjs.org/fast-json-stable-stringify/-/fast-json-stable-stringify-2.1.0.tgz",
@@ -3879,6 +3921,12 @@
       "dev": true,
       "license": "ISC"
     },
+    "node_modules/isstream": {
+      "version": "0.1.2",
+      "resolved": "https://registry.npmjs.org/isstream/-/isstream-0.1.2.tgz",
+      "integrity": "sha512-Yljz7ffyPbrLpLngrMtZ7NduUgVvi6wG9RJ9IUcyCd59YQ911PBJphODUcbOVbqYfxe1wuYf/LJ8PauMRwsM/g==",
+      "license": "MIT"
+    },
     "node_modules/istanbul-lib-coverage": {
       "version": "3.2.2",
       "resolved": "https://registry.npmjs.org/istanbul-lib-coverage/-/istanbul-lib-coverage-3.2.2.tgz",
@@ -5737,6 +5785,12 @@
         "node": ">=8"
       }
     },
+    "node_modules/lodash": {
+      "version": "4.17.21",
+      "resolved": "https://registry.npmjs.org/lodash/-/lodash-4.17.21.tgz",
+      "integrity": "sha512-v2kDEe57lecTulaDIuNTPy3Ry4gLGJ6Z1O3vE1krgXZNrsQ+LFTGHVxVjcXPs17LhbZVGedAJv8XZ1tvj5FvSg==",
+      "license": "MIT"
+    },
     "node_modules/lodash.debounce": {
       "version": "4.0.8",
       "resolved": "https://registry.npmjs.org/lodash.debounce/-/lodash.debounce-4.0.8.tgz",
@@ -5844,6 +5898,12 @@
       "dev": true,
       "license": "MIT"
     },
+    "node_modules/mute-stream": {
+      "version": "0.0.8",
+      "resolved": "https://registry.npmjs.org/mute-stream/-/mute-stream-0.0.8.tgz",
+      "integrity": "sha512-nnbWWOkoWyUsTjKrhgD0dcz22mdkSnpYqbEjIm2nhwhuxlSkpywJmBo8h0ZqJdkp73mb90SssHkN4rsRaBAfAA==",
+      "license": "ISC"
+    },
     "node_modules/natural-compare": {
       "version": "1.4.0",
       "resolved": "https://registry.npmjs.org/natural-compare/-/natural-compare-1.4.0.tgz",
@@ -6096,6 +6156,22 @@
         "url": "https://github.com/chalk/ansi-styles?sponsor=1"
       }
     },
+    "node_modules/prompt": {
+      "version": "1.3.0",
+      "resolved": "https://registry.npmjs.org/prompt/-/prompt-1.3.0.tgz",
+      "integrity": "sha512-ZkaRWtaLBZl7KKAKndKYUL8WqNT+cQHKRZnT4RYYms48jQkFw3rrBL+/N5K/KtdEveHkxs982MX2BkDKub2ZMg==",
+      "license": "MIT",
+      "dependencies": {
+        "@colors/colors": "1.5.0",
+        "async": "3.2.3",
+        "read": "1.0.x",
+        "revalidator": "0.1.x",
+        "winston": "2.x"
+      },
+      "engines": {
+        "node": ">= 6.0.0"
+      }
+    },
     "node_modules/prompts": {
       "version": "2.4.2",
       "resolved": "https://registry.npmjs.org/prompts/-/prompts-2.4.2.tgz",
@@ -6134,6 +6210,18 @@
       "dev": true,
       "license": "MIT"
     },
+    "node_modules/read": {
+      "version": "1.0.7",
+      "resolved": "https://registry.npmjs.org/read/-/read-1.0.7.tgz",
+      "integrity": "sha512-rSOKNYUmaxy0om1BNjMN4ezNT6VKK+2xF4GBhc81mkH7L60i6dp8qPYrkndNLT3QPphoII3maL9PVC9XmhHwVQ==",
+      "license": "ISC",
+      "dependencies": {
+        "mute-stream": "~0.0.4"
+      },
+      "engines": {
+        "node": ">=0.8"
+      }
+    },
     "node_modules/regenerate": {
       "version": "1.4.2",
       "resolved": "https://registry.npmjs.org/regenerate/-/regenerate-1.4.2.tgz",
@@ -6270,6 +6358,15 @@
         "node": ">=10"
       }
     },
+    "node_modules/revalidator": {
+      "version": "0.1.8",
+      "resolved": "https://registry.npmjs.org/revalidator/-/revalidator-0.1.8.tgz",
+      "integrity": "sha512-xcBILK2pA9oh4SiinPEZfhP8HfrB/ha+a2fTMyl7Om2WjlDVrOQy99N2MXXlUHqGJz4qEu2duXxHJjDWuK/0xg==",
+      "license": "Apache 2.0",
+      "engines": {
+        "node": ">= 0.4.0"
+      }
+    },
     "node_modules/semver": {
       "version": "6.3.1",
       "resolved": "https://registry.npmjs.org/semver/-/semver-6.3.1.tgz",
@@ -6355,6 +6452,15 @@
       "dev": true,
       "license": "BSD-3-Clause"
     },
+    "node_modules/stack-trace": {
+      "version": "0.0.10",
+      "resolved": "https://registry.npmjs.org/stack-trace/-/stack-trace-0.0.10.tgz",
+      "integrity": "sha512-KGzahc7puUKkzyMt+IqAep+TVNbKP+k2Lmwhub39m1AsTSkaDutx56aDCo+HLDzf/D26BIHTJWNiTG1KAJiQCg==",
+      "license": "MIT",
+      "engines": {
+        "node": "*"
+      }
+    },
     "node_modules/stack-utils": {
       "version": "2.0.6",
       "resolved": "https://registry.npmjs.org/stack-utils/-/stack-utils-2.0.6.tgz",
@@ -6670,6 +6776,32 @@
         "node": ">= 8"
       }
     },
+    "node_modules/winston": {
+      "version": "2.4.7",
+      "resolved": "https://registry.npmjs.org/winston/-/winston-2.4.7.tgz",
+      "integrity": "sha512-vLB4BqzCKDnnZH9PHGoS2ycawueX4HLqENXQitvFHczhgW2vFpSOn31LZtVr1KU8YTw7DS4tM+cqyovxo8taVg==",
+      "license": "MIT",
+      "dependencies": {
+        "async": "^2.6.4",
+        "colors": "1.0.x",
+        "cycle": "1.0.x",
+        "eyes": "0.1.x",
+        "isstream": "0.1.x",
+        "stack-trace": "0.0.x"
+      },
+      "engines": {
+        "node": ">= 0.10.0"
+      }
+    },
+    "node_modules/winston/node_modules/async": {
+      "version": "2.6.4",
+      "resolved": "https://registry.npmjs.org/async/-/async-2.6.4.tgz",
+      "integrity": "sha512-mzo5dfJYwAn29PeiJ0zvwTo04zj8HDJj0Mn8TD7sno7q12prdbnasKJHhkm2c1LgrhlJ0teaea8860oxi51mGA==",
+      "license": "MIT",
+      "dependencies": {
+        "lodash": "^4.17.14"
+      }
+    },
     "node_modules/wrap-ansi": {
       "version": "7.0.0",
       "resolved": "https://registry.npmjs.org/wrap-ansi/-/wrap-ansi-7.0.0.tgz",
diff --git a/package.json b/package.json
index 122233751..2bef5b587 100644
--- a/package.json
+++ b/package.json
@@ -10,11 +10,9 @@
   "devDependencies": {
     "@babel/core": "^7.25.8",
     "@babel/preset-env": "^7.25.8",
+    "@woowacourse/mission-utils": "^2.2.0",
     "babel-jest": "^29.6.0",
-    "jest": "^29.6.0"
-  },
-  "dependencies": {
-    "@woowacourse/mission-utils": "^2.2.0"
+    "jest": "^29.7.0"
   },
   "jest": {
     "transform": {
@@ -29,5 +27,8 @@
   "engines": {
     "npm": ">=10.8.2",
     "node": ">=20.17.0"
+  },
+  "dependencies": {
+    "prompt": "^1.3.0"
   }
 }
diff --git a/src/App.js b/src/App.js
index 091aa0a5d..e31c292a4 100644
--- a/src/App.js
+++ b/src/App.js
@@ -1,5 +1,42 @@
+import { Console } from "@woowacourse/mission-utils";
+
 class App {
-  async run() {}
-}
+  async run() {
+    try {
+
+      // 문자열을 입력받는다.
+      const input = await Console.readLineAsync("계산할 문자열을 입력해 주세요: ");
+
+      const result = this.calculate(input);
+      Console.print(`결과: ${result}`);
+    } catch (error) {
+      Console.print(error.message);
+      throw error;
+    }
+  }
+  calculate(input) {
+    //빈 문자열인지 검사
+    if (input === "") return 0;
 
-export default App;
+    //구분자 배열 생성
+    let delimiterArray = [',', ':'];
+    // 커스텀 구분자
+    const customDelimiter = input.match(/^\/\/(.)\\n/);
+    let numString = input;
+
+    if (customDelimiter) {
+      //커스텀 구분자 배열에 추가
+      delimiterArray.push(customDelimiter[1]);
+      numString = input.split('\\n')[1];
+    }
+
+    const nums = numString.split(new RegExp(`[${delimiterArray.join('')}]`)).map(Number);
+
+    //에러처리 => 음수랑 잘못된 문자열
+    if (nums.some((num) => num < 0 || isNaN(num))) {
+      throw new Error("[ERROR] 잘못된 입력 값 입니다.");
+    }
+    return nums.reduce((sum, num) => sum + num, 0);
+  }
+}
+export default App;
\ No newline at end of file