diff --git a/Cargo.lock b/Cargo.lock
index 5fc12bb5..809de233 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -49,6 +49,15 @@ version = "0.3.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "a4c527152e37cf757a3f78aae5a06fbeefdb07ccc535c980a3208ee3060dd544"
 
+[[package]]
+name = "arrayvec"
+version = "0.4.12"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "cd9fd44efafa8690358b7408d253adf110036b88f55672a933f01d616ad9b1b9"
+dependencies = [
+ "nodrop",
+]
+
 [[package]]
 name = "arrayvec"
 version = "0.5.2"
@@ -97,7 +106,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "afa748e348ad3be8263be728124b24a24f268266f6f5d58af9d75f6a40b5c587"
 dependencies = [
  "arrayref",
- "arrayvec",
+ "arrayvec 0.5.2",
  "constant_time_eq",
 ]
 
@@ -728,6 +737,7 @@ dependencies = [
  "lazy_static",
  "linked-hash-map",
  "lock_api",
+ "num-format",
  "num_cpus",
  "openssl",
  "pbr",
@@ -1109,6 +1119,12 @@ dependencies = [
  "windows-sys",
 ]
 
+[[package]]
+name = "nodrop"
+version = "0.1.14"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "72ef4a56884ca558e5ddb05a1d1e7e1bfd9a68d9ed024c21704cc98872dae1bb"
+
 [[package]]
 name = "num-derive"
 version = "0.3.3"
@@ -1120,6 +1136,16 @@ dependencies = [
  "syn",
 ]
 
+[[package]]
+name = "num-format"
+version = "0.4.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "bafe4179722c2894288ee77a9f044f02811c86af699344c498b0840c698a2465"
+dependencies = [
+ "arrayvec 0.4.12",
+ "itoa 0.4.8",
+]
+
 [[package]]
 name = "num-integer"
 version = "0.1.45"
diff --git a/Cargo.toml b/Cargo.toml
index fa6d4d7e..388881a4 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -37,6 +37,7 @@ bytesize = "1.*"
 hyper = "0.14.*"
 lock_api = "0.4.*"
 crossbeam-utils = "0.8.*"
+num-format = "*"
 
 [build-dependencies]
 static_vcruntime = "2.*"
diff --git a/src/afterfact.rs b/src/afterfact.rs
index 6752faa1..ee22a6e9 100644
--- a/src/afterfact.rs
+++ b/src/afterfact.rs
@@ -14,6 +14,7 @@ use lazy_static::lazy_static;
 use linked_hash_map::LinkedHashMap;
 
 use hashbrown::{HashMap, HashSet};
+use num_format::{ToFormattedString, Locale};
 use std::cmp::min;
 use std::error::Error;
 
@@ -334,7 +335,7 @@ fn emit_csv<W: std::io::Write>(
     write_color_buffer(
         &disp_wtr,
         get_writable_color(None),
-        &format!("Total events: {}", all_record_cnt),
+        &format!("Total events: {}", all_record_cnt.to_formatted_string(&Locale::en)),
         true,
     )
     .ok();
@@ -343,7 +344,7 @@ fn emit_csv<W: std::io::Write>(
         get_writable_color(None),
         &format!(
             "Data reduction: {} events ({:.2}%)",
-            reducted_record_cnt, reducted_percent
+            reducted_record_cnt.to_formatted_string(&Locale::en), reducted_percent
         ),
         true,
     )
@@ -440,7 +441,7 @@ fn _print_unique_results(
             "{} {}: {}",
             head_word,
             tail_word,
-            counts_by_level.iter().sum::<u128>(),
+            counts_by_level.iter().sum::<u128>().to_formatted_string(&Locale::en),
         ),
         true,
     )
@@ -452,7 +453,7 @@ fn _print_unique_results(
         }
         let output_raw_str = format!(
             "{} {} {}: {}",
-            head_word, level_name, tail_word, counts_by_level[i]
+            head_word, level_name, tail_word, counts_by_level[i].to_formatted_string(&Locale::en)
         );
         write_color_buffer(
             &BufferWriter::stdout(ColorChoice::Always),
@@ -482,7 +483,7 @@ fn _print_detection_summary_by_date(
         for (date, cnt) in detections_by_day {
             if cnt > &tmp_cnt {
                 exist_max_data = true;
-                max_detect_str = format!("{} ({})", date, cnt);
+                max_detect_str = format!("{} ({})", date, cnt.to_formatted_string(&Locale::en));
                 tmp_cnt = *cnt;
             }
         }
@@ -527,7 +528,7 @@ fn _print_detection_summary_by_computer(
         sorted_detections.sort_by(|a, b| (-a.1).cmp(&(-b.1)));
 
         for x in sorted_detections.iter().take(5) {
-            result_vec.push(format!("{} ({})", x.0, x.1));
+            result_vec.push(format!("{} ({})", x.0, x.1.to_formatted_string(&Locale::en)));
         }
         let result_str = if result_vec.is_empty() {
             "n/a".to_string()