diff --git a/src/components/common/spoiler/Spoiler.tsx b/src/components/common/spoiler/Spoiler.tsx
index 118566d1..5bf8a1d1 100644
--- a/src/components/common/spoiler/Spoiler.tsx
+++ b/src/components/common/spoiler/Spoiler.tsx
@@ -1,6 +1,6 @@
 import { MouseEvent as ReactMouseEvent } from 'react';
 import React, {
-  FC, memo, useCallback, useEffect,
+  FC, memo, useCallback, useEffect, useRef,
 } from '../../../lib/teact/teact';
 
 import { createClassNameBuilder } from '../../../util/buildClassName';
@@ -13,7 +13,9 @@ type OwnProps = {
   messageId?: number;
 };
 
-const AUTO_HIDE_TIMEOUT = 5000; // 5s
+const READING_SYMBOLS_PER_SECOND = 23; // Heuristics
+const MIN_HIDE_TIMEOUT = 5000; // 5s
+const MAX_HIDE_TIMEOUT = 60000; // 1m
 
 const actionsByMessageId: Map<number, {
   reveal: VoidFunction;
@@ -26,6 +28,9 @@ const Spoiler: FC<OwnProps> = ({
   children,
   messageId,
 }) => {
+  // eslint-disable-next-line no-null/no-null
+  const contentRef = useRef<HTMLDivElement>(null);
+
   const [isRevealed, reveal, conceal] = useFlag();
 
   const handleClick = useCallback((e: ReactMouseEvent<HTMLDivElement, MouseEvent>) => {
@@ -34,10 +39,14 @@ const Spoiler: FC<OwnProps> = ({
 
     actionsByMessageId.get(messageId!)?.forEach((actions) => actions.reveal());
 
+    const contentLength = contentRef.current!.innerText.length;
+    const readingMs = Math.round(contentLength / READING_SYMBOLS_PER_SECOND) * 1000;
+    const timeoutMs = Math.max(MIN_HIDE_TIMEOUT, Math.min(readingMs, MAX_HIDE_TIMEOUT));
+
     setTimeout(() => {
       actionsByMessageId.get(messageId!)?.forEach((actions) => actions.conceal());
       conceal();
-    }, AUTO_HIDE_TIMEOUT);
+    }, timeoutMs);
   }, [conceal, messageId]);
 
   useEffect(() => {
@@ -65,7 +74,7 @@ const Spoiler: FC<OwnProps> = ({
       )}
       onClick={messageId && !isRevealed ? handleClick : undefined}
     >
-      <span className={buildClassName('content')}>
+      <span className={buildClassName('content')} ref={contentRef}>
         {children}
       </span>
     </span>