diff --git a/akka-actor-typed/src/main/scala/akka/actor/typed/scaladsl/Routers.scala b/akka-actor-typed/src/main/scala/akka/actor/typed/scaladsl/Routers.scala
index c488d6a8ef..1efcca0e4b 100644
--- a/akka-actor-typed/src/main/scala/akka/actor/typed/scaladsl/Routers.scala
+++ b/akka-actor-typed/src/main/scala/akka/actor/typed/scaladsl/Routers.scala
@@ -145,7 +145,7 @@ trait PoolRouter[T] extends Behavior[T] {
    *
    * @param virtualNodesFactor This factor has to be greater or equal to 1. Assuming that the reader
    *                           knows what consistent hashing is
-   *                           (if not, please refer: http://www.tom-e-white.com/2007/11/consistent-hashing.html or wiki).
+   *                           (if not, please refer: https://www.tom-e-white.com/2007/11/consistent-hashing.html or wiki).
    *                           This number is responsible for creating additional,
    *                           virtual addresses for a provided set of routees,
    *                           so that in the total number of points on hashing ring
diff --git a/akka-actor/src/main/resources/reference.conf b/akka-actor/src/main/resources/reference.conf
index 32d2d10c00..2a09484dab 100644
--- a/akka-actor/src/main/resources/reference.conf
+++ b/akka-actor/src/main/resources/reference.conf
@@ -686,7 +686,7 @@ akka {
     debug {
       # enable function of Actor.loggable(), which is to log any received message
       # at DEBUG level, see the “Testing Actor Systems” section of the Akka
-      # Documentation at http://akka.io/docs
+      # Documentation at https://akka.io/docs
       receive = off
 
       # enable DEBUG logging of all AutoReceiveMessages (Kill, PoisonPill etc.)
diff --git a/akka-actor/src/main/scala/akka/actor/Actor.scala b/akka-actor/src/main/scala/akka/actor/Actor.scala
index 3265eb33e4..05f7b2254a 100644
--- a/akka-actor/src/main/scala/akka/actor/Actor.scala
+++ b/akka-actor/src/main/scala/akka/actor/Actor.scala
@@ -418,7 +418,7 @@ object Actor {
 
 /**
  * Actor base trait that should be extended by or mixed to create an Actor with the semantics of the 'Actor Model':
- * <a href="http://en.wikipedia.org/wiki/Actor_model">http://en.wikipedia.org/wiki/Actor_model</a>
+ * <a href="https://en.wikipedia.org/wiki/Actor_model">https://en.wikipedia.org/wiki/Actor_model</a>
  *
  * An actor has a well-defined (non-cyclic) life-cycle.
  *  - ''RUNNING'' (created and started actor) - can receive messages
diff --git a/akka-actor/src/main/scala/akka/actor/LightArrayRevolverScheduler.scala b/akka-actor/src/main/scala/akka/actor/LightArrayRevolverScheduler.scala
index 9b813cb523..145b5216af 100644
--- a/akka-actor/src/main/scala/akka/actor/LightArrayRevolverScheduler.scala
+++ b/akka-actor/src/main/scala/akka/actor/LightArrayRevolverScheduler.scala
@@ -85,7 +85,7 @@ class LightArrayRevolverScheduler(config: Config, log: LoggingAdapter, threadFac
    * Overridable for tests
    */
   protected def waitNanos(nanos: Long): Unit = {
-    // see http://www.javamex.com/tutorials/threads/sleep_issues.shtml
+    // see https://www.javamex.com/tutorials/threads/sleep_issues.shtml
     val sleepMs = if (Helpers.isWindows) (nanos + 4999999) / 10000000 * 10 else (nanos + 999999) / 1000000
     try Thread.sleep(sleepMs)
     catch {
diff --git a/akka-actor/src/main/scala/akka/io/IO.scala b/akka-actor/src/main/scala/akka/io/IO.scala
index 84cc145642..752b7f4c7f 100644
--- a/akka-actor/src/main/scala/akka/io/IO.scala
+++ b/akka-actor/src/main/scala/akka/io/IO.scala
@@ -9,7 +9,7 @@ import akka.actor._
 /**
  * Entry point to Akka’s IO layer.
  *
- * @see <a href="http://doc.akka.io/">the Akka online documentation</a>
+ * @see <a href="https://akka.io/docs/">the Akka online documentation</a>
  */
 object IO {
 
diff --git a/akka-actor/src/main/scala/akka/io/Tcp.scala b/akka-actor/src/main/scala/akka/io/Tcp.scala
index 398814f5fa..ada2ccf2b5 100644
--- a/akka-actor/src/main/scala/akka/io/Tcp.scala
+++ b/akka-actor/src/main/scala/akka/io/Tcp.scala
@@ -27,7 +27,7 @@ import akka.util.ccompat.JavaConverters._
  * TCP Extension for Akka’s IO layer.
  *
  * For a full description of the design and philosophy behind this IO
- * implementation please refer to <a href="http://doc.akka.io/">the Akka online documentation</a>.
+ * implementation please refer to <a href="https://akka.io/docs/">the Akka online documentation</a>.
  *
  * In order to open an outbound connection send a [[Tcp.Connect]] message
  * to the [[TcpExt#manager]].
diff --git a/akka-actor/src/main/scala/akka/io/Udp.scala b/akka-actor/src/main/scala/akka/io/Udp.scala
index 3c95692123..2fb699c182 100644
--- a/akka-actor/src/main/scala/akka/io/Udp.scala
+++ b/akka-actor/src/main/scala/akka/io/Udp.scala
@@ -26,7 +26,7 @@ import akka.util.ccompat._
  * from whom data can be received. For “connected” UDP mode see [[UdpConnected]].
  *
  * For a full description of the design and philosophy behind this IO
- * implementation please refer to <a href="http://doc.akka.io/">the Akka online documentation</a>.
+ * implementation please refer to <a href="https://akka.io/docs/">the Akka online documentation</a>.
  *
  * The Java API for generating UDP commands is available at [[UdpMessage]].
  */
diff --git a/akka-actor/src/main/scala/akka/io/dns/DnsSettings.scala b/akka-actor/src/main/scala/akka/io/dns/DnsSettings.scala
index 1cbb09aee6..ba455a181e 100644
--- a/akka-actor/src/main/scala/akka/io/dns/DnsSettings.scala
+++ b/akka-actor/src/main/scala/akka/io/dns/DnsSettings.scala
@@ -173,8 +173,8 @@ object DnsSettings {
       // Using jndi-dns to obtain the default name servers.
       //
       // See:
-      // - http://docs.oracle.com/javase/8/docs/technotes/guides/jndi/jndi-dns.html
-      // - http://mail.openjdk.java.net/pipermail/net-dev/2017-March/010695.html
+      // - https://docs.oracle.com/javase/8/docs/technotes/guides/jndi/jndi-dns.html
+      // - https://mail.openjdk.java.net/pipermail/net-dev/2017-March/010695.html
       val env = new util.Hashtable[String, String]
       env.put(Context.INITIAL_CONTEXT_FACTORY, "com.sun.jndi.dns.DnsContextFactory")
       env.put("java.naming.provider.url", "dns://")
diff --git a/akka-cluster-metrics/src/main/scala/akka/cluster/metrics/MetricsCollector.scala b/akka-cluster-metrics/src/main/scala/akka/cluster/metrics/MetricsCollector.scala
index be7c3229f7..1b3179208d 100644
--- a/akka-cluster-metrics/src/main/scala/akka/cluster/metrics/MetricsCollector.scala
+++ b/akka-cluster-metrics/src/main/scala/akka/cluster/metrics/MetricsCollector.scala
@@ -237,7 +237,7 @@ class SigarMetricsCollector(address: Address, decayFactor: Double, sigar: SigarP
 
   /**
    * (SIGAR) Returns the stolen CPU time. Relevant to virtual hosting environments.
-   * For details please see: <a href="http://en.wikipedia.org/wiki/CPU_time#Subdivision">Wikipedia - CPU time subdivision</a> and
+   * For details please see: <a href="https://en.wikipedia.org/wiki/CPU_time#Subdivision">Wikipedia - CPU time subdivision</a> and
    * <a href="https://www.datadoghq.com/2013/08/understanding-aws-stolen-cpu-and-how-it-affects-your-apps/">Understanding AWS stolen CPU and how it affects your apps</a>
    *
    * Creates a new instance each time.
diff --git a/akka-cluster-metrics/src/test/scala/akka/cluster/metrics/EWMASpec.scala b/akka-cluster-metrics/src/test/scala/akka/cluster/metrics/EWMASpec.scala
index bbaa5e7d2b..368aae70a5 100644
--- a/akka-cluster-metrics/src/test/scala/akka/cluster/metrics/EWMASpec.scala
+++ b/akka-cluster-metrics/src/test/scala/akka/cluster/metrics/EWMASpec.scala
@@ -53,7 +53,7 @@ class EWMASpec extends AkkaSpec(MetricsConfig.defaultEnabled) with MetricsCollec
     }
 
     "calculate alpha from half-life and collect interval" in {
-      // according to http://en.wikipedia.org/wiki/Moving_average#Exponential_moving_average
+      // according to https://en.wikipedia.org/wiki/Moving_average#Exponential_moving_average
       val expectedAlpha = 0.1
       // alpha = 2.0 / (1 + N)
       val n = 19
diff --git a/akka-distributed-data/src/main/scala/akka/cluster/ddata/GCounter.scala b/akka-distributed-data/src/main/scala/akka/cluster/ddata/GCounter.scala
index 8ae214f668..40cde4cb3e 100644
--- a/akka-distributed-data/src/main/scala/akka/cluster/ddata/GCounter.scala
+++ b/akka-distributed-data/src/main/scala/akka/cluster/ddata/GCounter.scala
@@ -31,7 +31,7 @@ object GCounter {
  * Implements a 'Growing Counter' CRDT, also called a 'G-Counter'.
  *
  * It is described in the paper
- * <a href="http://hal.upmc.fr/file/index/docid/555588/filename/techreport.pdf">A comprehensive study of Convergent and Commutative Replicated Data Types</a>.
+ * <a href="https://hal.inria.fr/file/index/docid/555588/filename/techreport.pdf">A comprehensive study of Convergent and Commutative Replicated Data Types</a>.
  *
  * A G-Counter is a increment-only counter (inspired by vector clocks) in
  * which only increment and merge are possible. Incrementing the counter
diff --git a/akka-testkit/src/test/scala/akka/testkit/metrics/MetricsKit.scala b/akka-testkit/src/test/scala/akka/testkit/metrics/MetricsKit.scala
index 8d46bf9e54..c5373469e5 100644
--- a/akka-testkit/src/test/scala/akka/testkit/metrics/MetricsKit.scala
+++ b/akka-testkit/src/test/scala/akka/testkit/metrics/MetricsKit.scala
@@ -22,7 +22,7 @@ import akka.testkit.metrics.reporter.AkkaConsoleReporter
  * Allows to easily measure performance / memory / file descriptor use in tests.
  *
  * WARNING: This trait should not be seen as utility for micro-benchmarking,
- * please refer to <a href="http://openjdk.java.net/projects/code-tools/jmh/">JMH</a> if that's what you're writing.
+ * please refer to <a href="https://openjdk.java.net/projects/code-tools/jmh/">JMH</a> if that's what you're writing.
  * This trait instead aims to give an high level overview as well as data for trend-analysis of long running tests.
  *
  * Reporting defaults to `ConsoleReporter`.