diff --git a/server/app/com/xsn/explorer/models/SynchronizationProgress.scala b/server/app/com/xsn/explorer/models/SynchronizationProgress.scala
new file mode 100644
index 00000000..7f1821ea
--- /dev/null
+++ b/server/app/com/xsn/explorer/models/SynchronizationProgress.scala
@@ -0,0 +1,5 @@
+package com.xsn.explorer.models
+
+case class SynchronizationProgress(total: Int, synced: Int) {
+  def missing: Int = Math.max(0, total - synced)
+}
diff --git a/server/app/com/xsn/explorer/services/StatisticsService.scala b/server/app/com/xsn/explorer/services/StatisticsService.scala
index cd97f570..06187f92 100644
--- a/server/app/com/xsn/explorer/services/StatisticsService.scala
+++ b/server/app/com/xsn/explorer/services/StatisticsService.scala
@@ -3,7 +3,7 @@ package com.xsn.explorer.services
 import com.alexitc.playsonify.core.FutureApplicationResult
 import com.alexitc.playsonify.core.FutureOr.Implicits.FutureOps
 import com.xsn.explorer.data.async.StatisticsFutureDataHandler
-import com.xsn.explorer.models.StatisticsDetails
+import com.xsn.explorer.models.{StatisticsDetails, SynchronizationProgress}
 import javax.inject.Inject
 import org.scalactic.{Bad, Good}
 
@@ -27,6 +27,18 @@ class StatisticsService @Inject()(xsnService: XSNService, statisticsFutureDataHa
     result.toFuture
   }
 
+  def getSynchronizationProgress: FutureApplicationResult[SynchronizationProgress] = {
+    val dbStats = statisticsFutureDataHandler.getStatistics()
+    val rpcBlock = xsnService.getLatestBlock()
+
+    val result = for {
+      stats <- dbStats.toFutureOr
+      latestBlock <- rpcBlock.toFutureOr
+    } yield SynchronizationProgress(total = latestBlock.height.int, synced = stats.blocks)
+
+    result.toFuture
+  }
+
   private def discardErrors[T](value: FutureApplicationResult[T]): FutureApplicationResult[Option[T]] = {
     value
       .map {
diff --git a/server/app/controllers/HealthController.scala b/server/app/controllers/HealthController.scala
index 9cb73705..5700e127 100644
--- a/server/app/controllers/HealthController.scala
+++ b/server/app/controllers/HealthController.scala
@@ -1,12 +1,22 @@
 package controllers
 
-import javax.inject.Inject
-
+import com.xsn.explorer.services.StatisticsService
 import controllers.common.{MyJsonController, MyJsonControllerComponents}
+import javax.inject.Inject
+import org.scalactic.Good
 
-class HealthController @Inject()(cc: MyJsonControllerComponents) extends MyJsonController(cc) {
+class HealthController @Inject()(cc: MyJsonControllerComponents, statsService: StatisticsService)
+    extends MyJsonController(cc) {
 
-  def check() = Action {
-    Ok
+  def check() = Action.async { _ =>
+    statsService.getSynchronizationProgress
+      .map {
+        case Good(progress) if progress.missing < 10 => Ok
+        case Good(progress) => InternalServerError(s"There are ${progress.missing} missing blocks")
+        case _ => InternalServerError("Failed to check sync progress")
+      }
+      .recover {
+        case _: Throwable => InternalServerError("Failed to check sync progress")
+      }
   }
 }
diff --git a/server/test/controllers/HealthControllerSpec.scala b/server/test/controllers/HealthControllerSpec.scala
index e30d9a55..bf605c0d 100644
--- a/server/test/controllers/HealthControllerSpec.scala
+++ b/server/test/controllers/HealthControllerSpec.scala
@@ -1,18 +1,48 @@
 package controllers
 
+import com.xsn.explorer.data.StatisticsBlockingDataHandler
+import com.xsn.explorer.helpers.DataGenerator
+import com.xsn.explorer.models._
+import com.xsn.explorer.models.values._
+import com.xsn.explorer.services.XSNService
 import controllers.common.MyAPISpec
+import org.mockito.MockitoSugar._
+import org.scalactic.Good
 import play.api.Application
+import play.api.inject.bind
 import play.api.test.Helpers._
 
+import scala.concurrent.Future
+
 class HealthControllerSpec extends MyAPISpec {
 
-  val application: Application = guiceApplicationBuilder.build()
+  private val xsnServiceMock = mock[XSNService]
+  private val statisticsDataHandlerMock = mock[StatisticsBlockingDataHandler]
+
+  val application: Application = guiceApplicationBuilder
+    .overrides(bind[XSNService].to(xsnServiceMock))
+    .overrides(bind[StatisticsBlockingDataHandler].to(statisticsDataHandlerMock))
+    .build()
 
   "GET /health" should {
     "return OK" in {
+      val latestXSNBlock = DataGenerator.randomBlock().copy(height = Height(19))
+      val stats = Statistics(10, 0, None, None)
+      when(xsnServiceMock.getLatestBlock()).thenReturn(Future.successful(Good(latestXSNBlock)))
+      when(statisticsDataHandlerMock.getStatistics()).thenReturn(Good(stats))
       val response = GET("/health")
 
       status(response) mustEqual OK
     }
+
+    "return Internal Server Error if there are 10 missing blocks" in {
+      val latestXSNBlock = DataGenerator.randomBlock().copy(height = Height(20))
+      val stats = Statistics(10, 0, None, None)
+      when(xsnServiceMock.getLatestBlock()).thenReturn(Future.successful(Good(latestXSNBlock)))
+      when(statisticsDataHandlerMock.getStatistics()).thenReturn(Good(stats))
+      val response = GET("/health")
+
+      status(response) mustEqual INTERNAL_SERVER_ERROR
+    }
   }
 }