diff --git a/server/client.js b/server/client.js
index 31f995f38..909c3e25b 100644
--- a/server/client.js
+++ b/server/client.js
@@ -9,6 +9,7 @@ const io = server.io;
 const { setting } = require("./util-server");
 const checkVersion = require("./check-version");
 const Database = require("./database");
+const Heartbeat = require("./model/heartbeat");
 
 /**
  * Send list of notification providers to client
@@ -54,7 +55,16 @@ async function sendHeartbeatList(socket, monitorID, toUser = false, overwrite =
         [monitorID]
     );
 
-    let result = list.reverse();
+    let result = list.reverse().map((row) => {
+        if (row.response) {
+            return {
+                ...row,
+                response: Heartbeat.decodeResponseValue(row.response),
+            };
+        }
+
+        return row;
+    });
 
     if (toUser) {
         io.to(socket.userID).emit("heartbeatList", monitorID, result, overwrite);
@@ -87,10 +97,12 @@ async function sendImportantHeartbeatList(socket, monitorID, toUser = false, ove
 
     timeLogger.print(`[Monitor: ${monitorID}] sendImportantHeartbeatList`);
 
+    const result = list.map((bean) => bean.toJSON());
+
     if (toUser) {
-        io.to(socket.userID).emit("importantHeartbeatList", monitorID, list, overwrite);
+        io.to(socket.userID).emit("importantHeartbeatList", monitorID, result, overwrite);
     } else {
-        socket.emit("importantHeartbeatList", monitorID, list, overwrite);
+        socket.emit("importantHeartbeatList", monitorID, result, overwrite);
     }
 }
 
diff --git a/server/model/heartbeat.js b/server/model/heartbeat.js
index d023571db..f7c036a2d 100644
--- a/server/model/heartbeat.js
+++ b/server/model/heartbeat.js
@@ -1,4 +1,5 @@
 const { BeanModel } = require("redbean-node/dist/bean-model");
+const zlib = require("node:zlib");
 
 /**
  * status:
@@ -36,9 +37,26 @@ class Heartbeat extends BeanModel {
             important: this._important,
             duration: this._duration,
             retries: this._retries,
-            response: this._response,
+            response: Heartbeat.decodeResponseValue(this._response),
         };
     }
+
+    /**
+     * Decode compressed response payload stored in database.
+     * @param {string|null} response Encoded response payload.
+     * @returns {string|null} Decoded response payload.
+     */
+    static decodeResponseValue(response) {
+        if (!response) {
+            return response;
+        }
+
+        try {
+            return zlib.gunzipSync(Buffer.from(response, "base64")).toString("utf8");
+        } catch (error) {
+            return response;
+        }
+    }
 }
 
 module.exports = Heartbeat;
diff --git a/server/model/monitor.js b/server/model/monitor.js
index 1eaf5997e..5404a47b5 100644
--- a/server/model/monitor.js
+++ b/server/model/monitor.js
@@ -56,6 +56,7 @@ const { CookieJar } = require("tough-cookie");
 const { HttpsCookieAgent } = require("http-cookie-agent/http");
 const https = require("https");
 const http = require("http");
+const zlib = require("node:zlib");
 const DomainExpiry = require("./domain_expiry");
 
 const rootCertificates = rootCertificatesFingerprints();
@@ -1149,7 +1150,7 @@ class Monitor extends BeanModel {
             responseData = responseData.substring(0, maxSize) + "... (truncated)";
         }
 
-        bean.response = responseData;
+        bean.response = zlib.gzipSync(Buffer.from(responseData, "utf8")).toString("base64");
     }
 
     /**
diff --git a/test/backend-test/test-monitor-response.js b/test/backend-test/test-monitor-response.js
index 4e7dbb018..01a35e27b 100644
--- a/test/backend-test/test-monitor-response.js
+++ b/test/backend-test/test-monitor-response.js
@@ -1,6 +1,7 @@
 const { describe, test } = require("node:test");
 const assert = require("node:assert");
 const Monitor = require("../../server/model/monitor");
+const Heartbeat = require("../../server/model/heartbeat");
 
 describe("Monitor response saving", () => {
     test("getSaveResponse and getSaveErrorResponse parse booleans", () => {
@@ -19,7 +20,7 @@ describe("Monitor response saving", () => {
         const bean = {};
         monitor.saveResponseData(bean, "abcdef");
 
-        assert.strictEqual(bean.response, "abcde... (truncated)");
+        assert.strictEqual(Heartbeat.decodeResponseValue(bean.response), "abcde... (truncated)");
     });
 
     test("saveResponseData stringifies objects", () => {
@@ -29,6 +30,6 @@ describe("Monitor response saving", () => {
         const bean = {};
         monitor.saveResponseData(bean, { ok: true });
 
-        assert.strictEqual(bean.response, JSON.stringify({ ok: true }));
+        assert.strictEqual(Heartbeat.decodeResponseValue(bean.response), JSON.stringify({ ok: true }));
     });
 });