diff --git a/cmd/rpi5-health/main.go b/cmd/rpi5-health/main.go
index 897de1e..b9f891b 100644
--- a/cmd/rpi5-health/main.go
+++ b/cmd/rpi5-health/main.go
@@ -6,6 +6,7 @@ import (
 	"rpi5-health/internal/http_internal"
 	"rpi5-health/internal/memory"
 	"rpi5-health/internal/processor"
+	"rpi5-health/internal/uptime"
 )
 
 func main() {
@@ -22,11 +23,13 @@ func main() {
 
 	_, kernel, usage, idle := processor.GetCPUInformation().Usage()
 
-	const HOUR = 60 * 60
-
 	log.Printf("Total time spent idling: %.2f%%\n", idle)
 	log.Printf("Total time spent in kernel mode: %.2f%%\n", kernel)
 	log.Printf("Total time spent in user mode: %.2f%%\n", usage)
 
+	uptime, _ := uptime.GetUptimeInformation()
+
+	log.Printf("Total uptime: %s", uptime.FormatSeconds())
+
 	cli.Listen()
 }
diff --git a/internal/uptime/linux_uptime.go b/internal/uptime/linux_uptime.go
new file mode 100644
index 0000000..215a7ee
--- /dev/null
+++ b/internal/uptime/linux_uptime.go
@@ -0,0 +1,50 @@
+//go:build linux
+
+package uptime
+
+import (
+	"bufio"
+	"fmt"
+	"os"
+	"strconv"
+	"strings"
+)
+
+func getLinuxUptime() (UptimeInformation, error) {
+	uptimeFile, err := os.Open("/proc/uptime")
+	if err != nil {
+		return UptimeInformation{}, fmt.Errorf("Could not find /proc/uptime. Are you sure you are on linux?")
+	}
+	defer uptimeFile.Close()
+
+	fileReader := bufio.NewScanner(uptimeFile)
+
+	var busyTime float64
+
+	fileReader.Scan()
+	if fileReader.Err() != nil {
+		return UptimeInformation{}, fmt.Errorf("Could not read /proc/uptime.")
+	}
+
+	data := fileReader.Text()
+
+	/*
+	 * fields[0] Time spent busy/suspended
+	 * fields[1] Time spent idling, it's combined from all CPU cores
+	 */
+	fields := strings.Split(data, " ")
+
+	busyTime, _ = strconv.ParseFloat(fields[0], 64)
+
+	return UptimeInformation{
+		uptime: busyTime,
+	}, nil
+}
+
+func GetUptimeInformation() (UptimeInformation, error) {
+	info, err := getLinuxUptime()
+	if err != nil {
+		return UptimeInformation{}, fmt.Errorf("Could not read uptime info. Error: %v", err)
+	}
+	return info, nil
+}
diff --git a/internal/uptime/uptime.go b/internal/uptime/uptime.go
new file mode 100644
index 0000000..8f06aab
--- /dev/null
+++ b/internal/uptime/uptime.go
@@ -0,0 +1,41 @@
+package uptime
+
+import (
+	"fmt"
+	"math"
+)
+
+type UptimeInformation struct {
+	uptime float64
+}
+
+func (uptimeInfo UptimeInformation) GetUptime() (seconds float64) {
+	return uptimeInfo.uptime
+}
+
+func (uptimeInfo UptimeInformation) FormatSeconds() string {
+	total := int64(math.Round(uptimeInfo.uptime))
+
+	if total < 60 {
+		return fmt.Sprintf("%d", total)
+	}
+	s := total % 60
+	m := (total / 60) % 60
+
+	if total < 3600 {
+		// e.g., 5:03
+		return fmt.Sprintf("%d:%02d", m, s)
+	}
+
+	h := (total / 3600) % 24
+
+	if total < 86400 {
+		// e.g., 2:05:03
+		return fmt.Sprintf("%d:%02d:%02d", h, m, s)
+	}
+
+	d := total / 86400
+
+	// e.g., 1:02:05:03
+	return fmt.Sprintf("%d:%02d:%02d:%02d", d, h, m, s)
+}
diff --git a/internal/uptime/win_uptime.go b/internal/uptime/win_uptime.go
new file mode 100644
index 0000000..b696cc8
--- /dev/null
+++ b/internal/uptime/win_uptime.go
@@ -0,0 +1,23 @@
+//go:build windows
+
+package uptime
+
+import (
+	"rpi5-health/internal/windows_system"
+
+	"golang.org/x/sys/windows"
+)
+
+type ULONGLONG uint64
+
+func getWinUptime(uptime *windows.LazyProc) (UptimeInformation, error) {
+	uptimeMetric, _, _ := uptime.Call()
+
+	uptimeSeconds := float64(uptimeMetric) / 1000.0
+
+	return UptimeInformation{uptime: uptimeSeconds}, nil
+}
+
+func GetUptimeInformation() (UptimeInformation, error) {
+	return getWinUptime(windows_system.GetWindowsTools().Uptime)
+}
diff --git a/internal/windows_system/win.go b/internal/windows_system/win.go
index 590fa4b..a4e73a5 100644
--- a/internal/windows_system/win.go
+++ b/internal/windows_system/win.go
@@ -21,16 +21,22 @@ type WindowsSystemCheckTools struct {
 	 * Windows processor information
 	 */
 	SystemTimes *windows.LazyProc
+	/*
+	 * Windows uptime metrics
+	 */
+	Uptime *windows.LazyProc
 }
 
 func GetWindowsTools() WindowsSystemCheckTools {
 	kernel32 := sync.OnceValue(func() *windows.LazyDLL { return windows.NewLazySystemDLL("kernel32.dll") })
 	procGlobalMemoryStatusEx := sync.OnceValue(func() *windows.LazyProc { return kernel32().NewProc("GlobalMemoryStatusEx") })
 	systemTimes := sync.OnceValue(func() *windows.LazyProc { return kernel32().NewProc("GetSystemTimes") })
+	uptime := sync.OnceValue(func() *windows.LazyProc { return kernel32().NewProc("GetTickCount64") })
 
 	return WindowsSystemCheckTools{
 		Kernel32:                 kernel32(),
 		ProcGlobalMemoryStatusEx: procGlobalMemoryStatusEx(),
 		SystemTimes:              systemTimes(),
+		Uptime:                   uptime(),
 	}
 }