diff --git a/docs/openapi.yaml b/docs/openapi.yaml
index 9e65d7b..04f99e8 100644
--- a/docs/openapi.yaml
+++ b/docs/openapi.yaml
@@ -607,6 +607,10 @@ components:
         login_message:
           description: Login message for signer.
           type: string
+        post_character_limit:
+          description: Post character limit.
+          type: integer
+          example: 5000
         blockchain_explorer_url:
           description: Blockchain explorer base URL.
           type: string
diff --git a/src/config.rs b/src/config.rs
index 7490a5f..fcc2892 100644
--- a/src/config.rs
+++ b/src/config.rs
@@ -65,6 +65,8 @@ fn default_environment() -> Environment { Environment::Development }
 
 fn default_log_level() -> LogLevel { LogLevel::Info }
 
+fn default_post_character_limit() -> usize { 2000 }
+
 #[derive(Clone, Deserialize)]
 pub struct BlockchainConfig {
     pub chain_id: String,
@@ -116,6 +118,9 @@ pub struct Config {
 
     pub login_message: String,
 
+    #[serde(default = "default_post_character_limit")]
+    pub post_character_limit: usize,
+
     // Blockchain integration
     pub blockchain: Option<BlockchainConfig>,
 
diff --git a/src/mastodon_api/instance/types.rs b/src/mastodon_api/instance/types.rs
index f679c61..f80a59b 100644
--- a/src/mastodon_api/instance/types.rs
+++ b/src/mastodon_api/instance/types.rs
@@ -13,6 +13,7 @@ pub struct InstanceInfo {
     registrations: bool,
 
     login_message: String,
+    post_character_limit: usize,
     blockchain_explorer_url: Option<String>,
     blockchain_contract_address: Option<String>,
     ipfs_gateway_url: Option<String>,
@@ -36,6 +37,7 @@ impl From<&Config> for InstanceInfo {
             version: get_full_api_version(&config.version),
             registrations: config.registrations_open,
             login_message: config.login_message.clone(),
+            post_character_limit: config.post_character_limit,
             blockchain_explorer_url: config.blockchain.as_ref()
                 .and_then(|val| val.explorer_url.clone()),
             blockchain_contract_address: config.blockchain.as_ref()
diff --git a/src/mastodon_api/statuses/views.rs b/src/mastodon_api/statuses/views.rs
index 1e469a6..8446ebe 100644
--- a/src/mastodon_api/statuses/views.rs
+++ b/src/mastodon_api/statuses/views.rs
@@ -62,7 +62,7 @@ async fn create_status(
     let current_user = get_current_user(db_client, auth.token()).await?;
     let instance = config.instance();
     let mut post_data = PostCreateData::try_from(data.into_inner())?;
-    post_data.clean()?;
+    post_data.clean(config.post_character_limit)?;
     // Mentions
     let mention_map = find_mentioned_profiles(
         db_client,
diff --git a/src/models/posts/types.rs b/src/models/posts/types.rs
index 51ee858..445cbf3 100644
--- a/src/models/posts/types.rs
+++ b/src/models/posts/types.rs
@@ -216,7 +216,10 @@ pub struct PostCreateData {
 
 impl PostCreateData {
     /// Validate and clean post data.
-    pub fn clean(&mut self) -> Result<(), ValidationError> {
+    pub fn clean(&mut self, character_limit: usize) -> Result<(), ValidationError> {
+        if self.content.chars().count() > character_limit {
+            return Err(ValidationError("post is too long"));
+        };
         let content_safe = clean_html(&self.content);
         let content_trimmed = content_safe.trim();
         if content_trimmed.is_empty() {
@@ -231,6 +234,8 @@ impl PostCreateData {
 mod tests {
     use super::*;
 
+    const POST_CHARACTER_LIMIT: usize = 1000;
+
     #[test]
     fn test_validate_post_data() {
         let mut post_data_1 = PostCreateData {
@@ -244,7 +249,7 @@ mod tests {
             object_id: None,
             created_at: None,
         };
-        assert_eq!(post_data_1.clean().is_ok(), false);
+        assert_eq!(post_data_1.clean(POST_CHARACTER_LIMIT).is_ok(), false);
     }
 
     #[test]
@@ -260,7 +265,7 @@ mod tests {
             object_id: None,
             created_at: None,
         };
-        assert_eq!(post_data_2.clean().is_ok(), true);
+        assert_eq!(post_data_2.clean(POST_CHARACTER_LIMIT).is_ok(), true);
         assert_eq!(post_data_2.content.as_str(), "test");
     }
 }