diff --git a/src/main.rs b/src/main.rs
index 01e559b..604dd4a 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -11,12 +11,12 @@ use std::fs;
 use std::time::SystemTime;
 use directories::ProjectDirs;
 use eframe::{CreationContext, Frame};
-use egui::{Context, RichText, TextEdit, Widget};
+use egui::{Color32, Context, RichText, TextEdit, Widget, WidgetText};
 use log::info;
 use native_dialog::MessageDialog;
 use simple_logger::SimpleLogger;
 use crate::notes::{Note, NoteMetadata};
-use crate::password::{check_password, generate_new_password};
+use crate::password::{check_password, entropy, generate_new_password};
 use crate::saving::Saving;
 
 mod notes;
@@ -223,7 +223,20 @@ impl eframe::App for App {
                     ui.label(RichText::new("after starting the app, the password will be tested against the latest note").italics());
 
                     ui.add_space(10.0);
-                    TextEdit::singleline(&mut self.password_buffer).password(true).ui(ui);
+                    ui.horizontal(|ui| {
+                        TextEdit::singleline(&mut self.password_buffer).password(true).ui(ui);
+                        if let Some(entropy) = entropy(&self.password_buffer) {
+                            let text = if entropy < 60_f64 {
+                                WidgetText::from(format!("entropy: {:.2}", entropy))
+                                    .color(Color32::from_rgb(220, 88, 42))
+                            } else {
+                                WidgetText::from(format!("entropy: {:.2}", entropy))
+                                    .color(Color32::from_rgb(144, 238, 144))
+                            };
+
+                            ui.label(text);
+                        }
+                    });
                     ui.add_space(7.5);
 
                     if ui.button("start app").clicked() {
diff --git a/src/password/mod.rs b/src/password/mod.rs
index 6aa3f70..dc05018 100644
--- a/src/password/mod.rs
+++ b/src/password/mod.rs
@@ -8,11 +8,27 @@ pub fn generate_new_password(password: &str) -> String {
     let mut output_key = [0u8; 256];
 
     hash_password(password.as_bytes(), &mut output);
-    Argon2::default().hash_password_into(&password.as_bytes(), &output, &mut output_key).unwrap();
+    Argon2::default().hash_password_into(password.as_bytes(), &output, &mut output_key).unwrap();
 
     hex::encode(output_key)
 }
 
+pub fn entropy(password: &str) -> Option<f64> {
+    if password.is_empty() {
+        return None;
+    }
+
+    let length = password.len() as f64;
+    let unique_characters = {
+        let mut unique_chars: Vec<char> = password.chars().collect();
+        unique_chars.dedup();
+
+        unique_chars.len()
+    } as f64;
+
+    Some(length * unique_characters.log2())
+}
+
 pub fn check_password(password: &str, note: &Note) -> anyhow::Result<String> {
     if note.decrypt(password).is_err() {
         let new_password = generate_new_password(password);