diff --git a/Cargo.lock b/Cargo.lock
index 2b5e8fd..1bd44ca 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -76,6 +76,12 @@ dependencies = [
  "libc",
 ]
 
+[[package]]
+name = "arrayvec"
+version = "0.7.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "96d30a06541fbafbc7f82ed10c06164cfbd2c401138f6addd8404629c4b16711"
+
 [[package]]
 name = "async-trait"
 version = "0.1.74"
@@ -243,6 +249,7 @@ dependencies = [
  "bytes",
  "chacha20",
  "dotenvy",
+ "duration-str",
  "env_logger",
  "futures-util",
  "hex",
@@ -529,6 +536,20 @@ version = "0.15.7"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "1aaf95b3e5c8f23aa320147307562d361db0ae0d51242340f558153b4eb2439b"
 
+[[package]]
+name = "duration-str"
+version = "0.7.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "5e172e85f305d6a442b250bf40667ffcb91a24f52c9a1ca59e2fa991ac9b7790"
+dependencies = [
+ "chrono",
+ "nom",
+ "rust_decimal",
+ "serde",
+ "thiserror",
+ "time",
+]
+
 [[package]]
 name = "dyn-clone"
 version = "1.0.14"
@@ -1154,6 +1175,12 @@ version = "0.3.17"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "6877bb514081ee2a7ff5ef9de3281f14a4dd4bceac4c09388074a6b5df8a139a"
 
+[[package]]
+name = "minimal-lexical"
+version = "0.2.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "68354c5c6bd36d73ff3feceb05efa59b6acb7626617f4962be322a825e61f79a"
+
 [[package]]
 name = "miniz_oxide"
 version = "0.7.1"
@@ -1192,6 +1219,16 @@ dependencies = [
  "version_check",
 ]
 
+[[package]]
+name = "nom"
+version = "7.1.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d273983c5a657a70a3e8f2a01329822f3b8c8172b73826411a55751e404a0a4a"
+dependencies = [
+ "memchr",
+ "minimal-lexical",
+]
+
 [[package]]
 name = "num-bigint"
 version = "0.4.4"
@@ -1728,6 +1765,16 @@ dependencies = [
  "zeroize",
 ]
 
+[[package]]
+name = "rust_decimal"
+version = "1.32.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a4c4216490d5a413bc6d10fa4742bd7d4955941d062c0ef873141d6b0e7b30fd"
+dependencies = [
+ "arrayvec",
+ "num-traits",
+]
+
 [[package]]
 name = "rustc-demangle"
 version = "0.1.23"
diff --git a/Cargo.toml b/Cargo.toml
index f26cc6c..fa02fc0 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -12,6 +12,7 @@ futures-util = "0.3"
 axum = {version="0.6", features=["macros", "headers", "multipart"]}
 serde = "1.0"
 toml = "0.8"
+duration-str = "0.7.0"
 render = { git="https://github.com/render-rs/render.rs" }
 thiserror = "1.0"
 rand = "0.8"
diff --git a/src/main.rs b/src/main.rs
index c50653c..6de1def 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -1,9 +1,10 @@
 #![deny(clippy::unwrap_used)]
+use duration_str::{deserialize_option_duration, parse_std};
 use std::{
     borrow::Borrow,
     env,
     str::FromStr,
-    time::{SystemTime, UNIX_EPOCH},
+    time::{Duration, SystemTime, UNIX_EPOCH},
 };
 
 use axum::{
@@ -196,7 +197,8 @@ async fn get_index(
 
 #[derive(Deserialize)]
 pub struct PostQuery {
-    ttl: Option<u64>,
+    #[serde(deserialize_with = "deserialize_option_duration")]
+    ttl: Option<Duration>,
 }
 
 async fn post_item(
@@ -226,7 +228,7 @@ async fn post_item(
         let mut etag_hasher = Sha3_256::new();
         let mut size: u64 = 0;
 
-        let mut ttl = params.ttl.unwrap_or(24 * 3600);
+        let mut ttl = params.ttl.unwrap_or(Duration::from_secs(24 * 3600));
 
         match data {
             MultipartOrStream::Stream(mut stream) => {
@@ -267,7 +269,7 @@ async fn post_item(
                     }
                     if field.name().unwrap_or_default() == "ttl" {
                         if let Some(mp_ttl) =
-                            field.text().await.ok().and_then(|x| x.parse::<u64>().ok())
+                            field.text().await.ok().and_then(|x| parse_std(x).ok())
                         {
                             ttl = mp_ttl;
                         }
@@ -277,16 +279,17 @@ async fn post_item(
         }
         writer.flush().await?;
 
-        let now = SystemTime::now().duration_since(UNIX_EPOCH)?.as_secs();
-        let expires_at = match u64::MAX - ttl > now {
-            true => now + ttl,
-            false => u64::MAX,
-        };
+        if let Some(expires_at) = SystemTime::now()
+            .duration_since(UNIX_EPOCH)?
+            .checked_add(ttl)
+            .map(|x| x.as_secs())
+        {
+            metadata.expires_at = expires_at;
+        }
 
         metadata.etag = Some(hex::encode(etag_hasher.finalize()));
         metadata.size = Some(size);
 
-        metadata.expires_at = expires_at;
         metadata.to_file(&metadata_path).await?;
 
         app_state