diff --git a/src/config.rs b/src/config.rs
index 08a0bc4..b2cf8e1 100644
--- a/src/config.rs
+++ b/src/config.rs
@@ -61,7 +61,7 @@ pub fn load_dates_from_cache(cache_file: &str) -> Result<Option<BTreeMap<DateTim
 }
 
 pub fn save_dates_to_cache(cache_file: &str, dates: &BTreeMap<DateTime<Utc>, u64>) -> Result<()> {
-    let json = serde_json::to_string(&dates)?;
+    let json = serde_json::to_string_pretty(&dates)?;
     fs::write(cache_file, json.as_bytes())?;
     Ok(())
 }
diff --git a/src/main.rs b/src/main.rs
index 1d5d7e6..09ad864 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -163,7 +163,7 @@ async fn run() -> Result<()> {
 
     // Write out the cache file if necessary.
     if !args.dry_run && cache_changed {
-        let json = serde_json::to_string(&post_cache)?;
+        let json = serde_json::to_string_pretty(&post_cache)?;
         fs::write(post_cache_file, json.as_bytes())?;
     }