diff --git a/src/cfg.rs b/src/cfg.rs
index 5e90339..e420f30 100755
--- a/src/cfg.rs
+++ b/src/cfg.rs
@@ -68,4 +68,8 @@ pub struct BoardCfg {
     pub require_thread_file: bool,
     pub require_reply_content: bool,
     pub require_reply_file: bool,
+    pub antispam: bool,
+    pub antispam_ip: i64,
+    pub antispam_content: i64,
+    pub antispam_both: i64,
 }
diff --git a/src/error.rs b/src/error.rs
index bac192a..878c4c5 100755
--- a/src/error.rs
+++ b/src/error.rs
@@ -76,6 +76,8 @@ pub enum NekrochanError {
     AlreadyAppealedError,
     #[error("Tento ban nelze odvolat.")]
     UnappealableError,
+    #[error("Tvůj příspěvek vypadá jako spam.")]
+    FloodError,
     // 500
     #[error("Nadnástěnka nebyla inicializována.")]
     OverboardError,
@@ -235,6 +237,7 @@ impl ResponseError for NekrochanError {
             | NekrochanError::IncorrectCaptchaError
             | NekrochanError::IncorrectPasswordError(_) => StatusCode::UNAUTHORIZED,
             NekrochanError::HeaderError(_) => StatusCode::BAD_GATEWAY,
+            NekrochanError::FloodError => StatusCode::TOO_MANY_REQUESTS,
             NekrochanError::OverboardError | NekrochanError::InternalError => {
                 StatusCode::INTERNAL_SERVER_ERROR
             }
diff --git a/src/web/actions/create_post.rs b/src/web/actions/create_post.rs
index 2cdbf05..d14f12a 100644
--- a/src/web/actions/create_post.rs
+++ b/src/web/actions/create_post.rs
@@ -3,8 +3,11 @@ use actix_web::{
     cookie::Cookie, http::StatusCode, post, web::Data, HttpRequest, HttpResponse,
     HttpResponseBuilder,
 };
+use chrono::{Duration, Utc};
 use pwhash::bcrypt::hash;
+use redis::AsyncCommands;
 use sha256::digest;
+use std::{collections::HashSet, net::IpAddr};
 
 use crate::{
     ctx::Ctx,
@@ -171,6 +174,10 @@ pub async fn create_post(
     )
     .await?;
 
+    if board.config.antispam {
+        check_spam(&ctx, &board, ip, content_nomarkup.clone()).await?;
+    }
+
     if form.files.len() > board.config.0.file_limit {
         return Err(NekrochanError::FileLimitError(board.config.0.file_limit));
     }
@@ -248,3 +255,53 @@ pub async fn create_post(
 
     Ok(res)
 }
+
+pub async fn check_spam(
+    ctx: &Ctx,
+    board: &Board,
+    ip: IpAddr,
+    content_nomarkup: String,
+) -> Result<(), NekrochanError> {
+    let ip_key = format!("by_ip:{ip}");
+    let content_key = format!("by_content:{}", digest(content_nomarkup));
+
+    let antispam_ip = (Utc::now() - Duration::seconds(board.config.antispam_ip)).timestamp_micros();
+    let antispam_content =
+        (Utc::now() - Duration::seconds(board.config.antispam_content)).timestamp_micros();
+    let antispam_both =
+        (Utc::now() - Duration::seconds(board.config.antispam_both)).timestamp_micros();
+
+    let ip_posts: HashSet<String> = ctx
+        .cache()
+        .zrangebyscore(&ip_key, antispam_ip, "+inf")
+        .await?;
+    let content_posts: HashSet<String> = ctx
+        .cache()
+        .zrangebyscore(&content_key, antispam_content, "+inf")
+        .await?;
+
+    let ip_posts2: HashSet<String> = ctx
+        .cache()
+        .zrangebyscore(&ip_key, antispam_both, "+inf")
+        .await?;
+    let content_posts2: HashSet<String> = ctx
+        .cache()
+        .zrangebyscore(&content_key, antispam_both, "+inf")
+        .await?;
+
+    let both_posts = ip_posts2.intersection(&content_posts2);
+
+    if !ip_posts.is_empty() {
+        return Err(NekrochanError::FloodError);
+    }
+
+    if !content_posts.is_empty() {
+        return Err(NekrochanError::FloodError);
+    }
+
+    if both_posts.count() != 0 {
+        return Err(NekrochanError::FloodError);
+    }
+
+    Ok(())
+}
diff --git a/src/web/actions/user_post_actions.rs b/src/web/actions/user_post_actions.rs
index f2d92a6..4e82e3e 100644
--- a/src/web/actions/user_post_actions.rs
+++ b/src/web/actions/user_post_actions.rs
@@ -1,8 +1,7 @@
-use std::fmt::Write;
-
 use actix_web::{post, web::Data, HttpRequest, HttpResponse};
 use pwhash::bcrypt::verify;
 use serde::Deserialize;
+use std::fmt::Write;
 
 use crate::{
     ctx::Ctx,
diff --git a/src/web/staff/actions/update_board_config.rs b/src/web/staff/actions/update_board_config.rs
index d4af5fd..e8ad34f 100755
--- a/src/web/staff/actions/update_board_config.rs
+++ b/src/web/staff/actions/update_board_config.rs
@@ -24,6 +24,10 @@ pub struct UpdateBoardConfigForm {
     require_thread_file: Option<String>,
     require_reply_content: Option<String>,
     require_reply_file: Option<String>,
+    antispam: Option<String>,
+    antispam_ip: i64,
+    antispam_content: i64,
+    antispam_both: i64,
 }
 
 #[post("/staff/actions/update-board-config")]
@@ -58,6 +62,10 @@ pub async fn update_board_config(
     let require_thread_file = form.require_thread_file.is_some();
     let require_reply_content = form.require_reply_content.is_some();
     let require_reply_file = form.require_reply_file.is_some();
+    let antispam = form.antispam.is_some();
+    let antispam_ip = form.antispam_ip;
+    let antispam_content = form.antispam_content;
+    let antispam_both = form.antispam_both;
 
     let config = BoardCfg {
         anon_name,
@@ -75,6 +83,10 @@ pub async fn update_board_config(
         require_thread_file,
         require_reply_content,
         require_reply_file,
+        antispam,
+        antispam_ip,
+        antispam_content,
+        antispam_both
     };
 
     board.update_config(&ctx, config).await?;
diff --git a/templates/staff/board-config.html b/templates/staff/board-config.html
index 39c42e4..8e6e76b 100755
--- a/templates/staff/board-config.html
+++ b/templates/staff/board-config.html
@@ -145,6 +145,30 @@
             </td>
         </tr>
 
+        <tr>
+            <td class="label">Antispam</td>
+            <td>
+                <div class="input-wrapper">
+                    <input name="antispam" type="checkbox" {% if board.config.0.antispam %}checked="checked"{% endif %}>
+                </div>
+            </td>
+        </tr>
+
+        <tr>
+            <td class="label">Interval antispamu (IP)</td>
+            <td><input name="antispam_ip" type="number" min="0" value="{{ board.config.0.antispam_ip }}" required="required"></td>
+        </tr>
+
+        <tr>
+            <td class="label">Interval antispamu (Obsah)</td>
+            <td><input name="antispam_content" type="number" min="0" value="{{ board.config.0.antispam_content }}" required="required"></td>
+        </tr>
+
+        <tr>
+            <td class="label">Interval antispamu (IP+Obsah)</td>
+            <td><input name="antispam_both" type="number" min="0" value="{{ board.config.0.antispam_both }}" required="required"></td>
+        </tr>
+
         <tr>
             <td class="submit" colspan="2"><input class="button" type="submit" value="Uložit"></td>
         </tr>