diff --git a/Aware.xcodeproj/project.pbxproj b/Aware.xcodeproj/project.pbxproj
index 988be03..aeb7d3c 100644
--- a/Aware.xcodeproj/project.pbxproj
+++ b/Aware.xcodeproj/project.pbxproj
@@ -11,6 +11,9 @@
 		036EBD191C1408C200121D0B /* AppDelegate.swift in Sources */ = {isa = PBXBuildFile; fileRef = 036EBD181C1408C200121D0B /* AppDelegate.swift */; };
 		036EBD1B1C1408C200121D0B /* Assets.xcassets in Resources */ = {isa = PBXBuildFile; fileRef = 036EBD1A1C1408C200121D0B /* Assets.xcassets */; };
 		036EBD1E1C1408C200121D0B /* MainMenu.xib in Resources */ = {isa = PBXBuildFile; fileRef = 036EBD1C1C1408C200121D0B /* MainMenu.xib */; };
+		03F9E2311C24CCA8001DBE86 /* NSTimeIntervalFormatter.swift in Sources */ = {isa = PBXBuildFile; fileRef = 03F9E2301C24CCA8001DBE86 /* NSTimeIntervalFormatter.swift */; };
+		03F9E2331C24CD2E001DBE86 /* NSTimeIntervalFormatterTests.swift in Sources */ = {isa = PBXBuildFile; fileRef = 03F9E2321C24CD2E001DBE86 /* NSTimeIntervalFormatterTests.swift */; };
+		03F9E2341C24CDAB001DBE86 /* NSTimeIntervalFormatter.swift in Sources */ = {isa = PBXBuildFile; fileRef = 03F9E2301C24CCA8001DBE86 /* NSTimeIntervalFormatter.swift */; };
 /* End PBXBuildFile section */
 
 /* Begin PBXContainerItemProxy section */
@@ -32,6 +35,8 @@
 		036EBD1F1C1408C200121D0B /* Info.plist */ = {isa = PBXFileReference; lastKnownFileType = text.plist.xml; path = Info.plist; sourceTree = "<group>"; };
 		03F9E2261C24CAD3001DBE86 /* AwareTests.xctest */ = {isa = PBXFileReference; explicitFileType = wrapper.cfbundle; includeInIndex = 0; path = AwareTests.xctest; sourceTree = BUILT_PRODUCTS_DIR; };
 		03F9E22A1C24CAD3001DBE86 /* Info.plist */ = {isa = PBXFileReference; lastKnownFileType = text.plist.xml; path = Info.plist; sourceTree = "<group>"; };
+		03F9E2301C24CCA8001DBE86 /* NSTimeIntervalFormatter.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = NSTimeIntervalFormatter.swift; sourceTree = "<group>"; };
+		03F9E2321C24CD2E001DBE86 /* NSTimeIntervalFormatterTests.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = NSTimeIntervalFormatterTests.swift; sourceTree = "<group>"; };
 /* End PBXFileReference section */
 
 /* Begin PBXFrameworksBuildPhase section */
@@ -74,6 +79,7 @@
 			isa = PBXGroup;
 			children = (
 				036EBD181C1408C200121D0B /* AppDelegate.swift */,
+				03F9E2301C24CCA8001DBE86 /* NSTimeIntervalFormatter.swift */,
 				0337E7861C14E37B003A8150 /* NSTimer+Block.swift */,
 				036EBD1A1C1408C200121D0B /* Assets.xcassets */,
 				036EBD1C1C1408C200121D0B /* MainMenu.xib */,
@@ -85,6 +91,7 @@
 		03F9E2271C24CAD3001DBE86 /* AwareTests */ = {
 			isa = PBXGroup;
 			children = (
+				03F9E2321C24CD2E001DBE86 /* NSTimeIntervalFormatterTests.swift */,
 				03F9E22A1C24CAD3001DBE86 /* Info.plist */,
 			);
 			path = AwareTests;
@@ -190,6 +197,7 @@
 			isa = PBXSourcesBuildPhase;
 			buildActionMask = 2147483647;
 			files = (
+				03F9E2311C24CCA8001DBE86 /* NSTimeIntervalFormatter.swift in Sources */,
 				036EBD191C1408C200121D0B /* AppDelegate.swift in Sources */,
 				0337E7871C14E37B003A8150 /* NSTimer+Block.swift in Sources */,
 			);
@@ -199,6 +207,8 @@
 			isa = PBXSourcesBuildPhase;
 			buildActionMask = 2147483647;
 			files = (
+				03F9E2331C24CD2E001DBE86 /* NSTimeIntervalFormatterTests.swift in Sources */,
+				03F9E2341C24CDAB001DBE86 /* NSTimeIntervalFormatter.swift in Sources */,
 			);
 			runOnlyForDeploymentPostprocessing = 0;
 		};
diff --git a/Aware/AppDelegate.swift b/Aware/AppDelegate.swift
index 08ed3d1..4a27a2f 100644
--- a/Aware/AppDelegate.swift
+++ b/Aware/AppDelegate.swift
@@ -49,15 +49,6 @@ class AppDelegate: NSObject, NSApplicationDelegate {
         }
 
         let duration = NSDate().timeIntervalSinceDate(timerStart)
-        statusItem.button!.title = formatDuration(duration)
-    }
-
-    func formatDuration(duration: NSTimeInterval) -> String {
-        let minutes = NSInteger(duration) / 60
-        if minutes < 60 {
-            return "\(minutes)m"
-        } else {
-            return "\(minutes / 60)h \(minutes % 60)m"
-        }
+        statusItem.button!.title = NSTimeIntervalFormatter().stringFromTimeInterval(duration)
     }
 }
diff --git a/Aware/NSTimeIntervalFormatter.swift b/Aware/NSTimeIntervalFormatter.swift
new file mode 100644
index 0000000..6c2b17b
--- /dev/null
+++ b/Aware/NSTimeIntervalFormatter.swift
@@ -0,0 +1,20 @@
+import Foundation
+
+class NSTimeIntervalFormatter {
+    /**
+        Formats time interval as a human readable duration string.
+
+        - Parameters:
+            - interval: The time interval in seconds.
+
+        - Returns: A `String`.
+     */
+    func stringFromTimeInterval(interval: NSTimeInterval) -> String {
+        let minutes = NSInteger(interval) / 60
+        if minutes < 60 {
+            return "\(minutes)m"
+        } else {
+            return "\(minutes / 60)h \(minutes % 60)m"
+        }
+    }
+}
diff --git a/AwareTests/NSTimeIntervalFormatterTests.swift b/AwareTests/NSTimeIntervalFormatterTests.swift
new file mode 100644
index 0000000..975e971
--- /dev/null
+++ b/AwareTests/NSTimeIntervalFormatterTests.swift
@@ -0,0 +1,33 @@
+import XCTest
+
+class NSTimeIntervalFormatterTests: XCTestCase {
+    func testStringFromTimeInterval() {
+        let formatter = NSTimeIntervalFormatter()
+
+        XCTAssertEqual(formatter.stringFromTimeInterval(0), "0m")
+        XCTAssertEqual(formatter.stringFromTimeInterval(1), "0m")
+        XCTAssertEqual(formatter.stringFromTimeInterval(30), "0m")
+        XCTAssertEqual(formatter.stringFromTimeInterval(59), "0m")
+
+        XCTAssertEqual(formatter.stringFromTimeInterval(60), "1m")
+        XCTAssertEqual(formatter.stringFromTimeInterval(61), "1m")
+        XCTAssertEqual(formatter.stringFromTimeInterval(119), "1m")
+
+        XCTAssertEqual(formatter.stringFromTimeInterval(120), "2m")
+        XCTAssertEqual(formatter.stringFromTimeInterval(300), "5m")
+        XCTAssertEqual(formatter.stringFromTimeInterval(900), "15m")
+        XCTAssertEqual(formatter.stringFromTimeInterval(1800), "30m")
+        XCTAssertEqual(formatter.stringFromTimeInterval(2700), "45m")
+        XCTAssertEqual(formatter.stringFromTimeInterval(3540), "59m")
+        XCTAssertEqual(formatter.stringFromTimeInterval(3599), "59m")
+
+        XCTAssertEqual(formatter.stringFromTimeInterval(3600), "1h 0m")
+        XCTAssertEqual(formatter.stringFromTimeInterval(3601), "1h 0m")
+        XCTAssertEqual(formatter.stringFromTimeInterval(3660), "1h 1m")
+        XCTAssertEqual(formatter.stringFromTimeInterval(4500), "1h 15m")
+        XCTAssertEqual(formatter.stringFromTimeInterval(5400), "1h 30m")
+        XCTAssertEqual(formatter.stringFromTimeInterval(6300), "1h 45m")
+
+        XCTAssertEqual(formatter.stringFromTimeInterval(7200), "2h 0m")
+    }
+}