diff --git a/types/ip-subnet-calculator/index.d.ts b/types/ip-subnet-calculator/index.d.ts
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index 0000000000..e3158233b3
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+++ b/types/ip-subnet-calculator/index.d.ts
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+// Type definitions for ip-subnet-calculator 1.1
+// Project: https://github.com/franksrevenge/IPSubnetCalculator
+// Definitions by: dahool <https://github.com/dahool>
+// Definitions: https://github.com/DefinitelyTyped/DefinitelyTyped
+
+export as namespace IpSubnetCalculator;
+
+export function calculate(ipStart: string|number, ipEnd: string|number): SubnetResult[];
+export function calculateSubnetMask(ip: string|number, prefixSize: number): SubnetResult;
+export function calculateCIDRPrefix(ip: string|number, subnetMask: string|number): SubnetResult;
+
+export function isIp(ipStr: string): boolean;
+export function isDecimalIp(ipNum: number): boolean;
+
+export function toDecimal(ip: string|number): number;
+export function toString(num: string|number): string;
+
+export interface SubnetResult {
+    ipLow: number;
+    ipLowStr: string;
+    ipHigh: number;
+    ipHighStr: string;
+    prefixMask: number;
+    prefixMaskStr: string;
+    prefixSize: number;
+    invertedMask: number;
+    invertedMaskStr: string;
+    invertedSize: number;
+}
diff --git a/types/ip-subnet-calculator/ip-subnet-calculator-tests.ts b/types/ip-subnet-calculator/ip-subnet-calculator-tests.ts
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+++ b/types/ip-subnet-calculator/ip-subnet-calculator-tests.ts
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+import * as IpSubnetCalculator from "ip-subnet-calculator";
+
+IpSubnetCalculator.calculate("", ""); // $ExpectType SubnetResult[]
+IpSubnetCalculator.calculateSubnetMask("", 1); // $ExpectType SubnetResult
+IpSubnetCalculator.calculateCIDRPrefix("", 1); // $ExpectType SubnetResult
+
+IpSubnetCalculator.isIp(""); // $ExpectType boolean
+IpSubnetCalculator.isDecimalIp(0); // $ExpectType boolean
+
+IpSubnetCalculator.toDecimal(""); // $ExpectType number
+IpSubnetCalculator.toString(0); // $ExpectType string
diff --git a/types/ip-subnet-calculator/tsconfig.json b/types/ip-subnet-calculator/tsconfig.json
new file mode 100644
index 0000000000..74284388ce
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+++ b/types/ip-subnet-calculator/tsconfig.json
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+{
+    "compilerOptions": {
+        "module": "commonjs",
+        "lib": [
+            "es6"
+        ],
+        "noImplicitAny": true,
+        "noImplicitThis": true,
+        "strictFunctionTypes": true,
+        "strictNullChecks": true,
+        "baseUrl": "../",
+        "typeRoots": [
+            "../"
+        ],
+        "types": [],
+        "noEmit": true,
+        "forceConsistentCasingInFileNames": true
+    },
+    "files": [
+        "index.d.ts",
+        "ip-subnet-calculator-tests.ts"
+    ]
+}
diff --git a/types/ip-subnet-calculator/tslint.json b/types/ip-subnet-calculator/tslint.json
new file mode 100644
index 0000000000..3db14f85ea
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+++ b/types/ip-subnet-calculator/tslint.json
@@ -0,0 +1 @@
+{ "extends": "dtslint/dt.json" }