diff --git a/Cargo.lock b/Cargo.lock
index beba0da..75340ae4 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -199,6 +199,12 @@ dependencies = [
  "syn",
 ]
 
+[[package]]
+name = "either"
+version = "1.6.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "cd56b59865bce947ac5958779cfa508f6c3b9497cc762b7e24a12d11ccde2c4f"
+
 [[package]]
 name = "failure"
 version = "0.1.8"
@@ -259,6 +265,15 @@ version = "1.0.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "b9e0384b61958566e926dc50660321d12159025e767c18e043daf26b70104c39"
 
+[[package]]
+name = "itertools"
+version = "0.9.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "284f18f85651fe11e8a991b2adb42cb078325c996ed026d994719efcfca1d54b"
+dependencies = [
+ "either",
+]
+
 [[package]]
 name = "itoa"
 version = "0.4.6"
@@ -608,6 +623,7 @@ dependencies = [
  "chrono",
  "clap",
  "crossterm",
+ "itertools",
  "rand",
  "serde",
  "serde_json",
diff --git a/Cargo.toml b/Cargo.toml
index 4fd0043..a4edf88 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -18,6 +18,7 @@ default = ["crossterm-backend"]
 crossterm-backend = ["tui/crossterm", "crossterm"]
 
 [dependencies]
+itertools = "0.9"
 serde = { version = "1", features = ["derive"] }
 serde_json = "1"
 clap = "2.33"
diff --git a/src/app.rs b/src/app.rs
index 675a772..b6cf447 100644
--- a/src/app.rs
+++ b/src/app.rs
@@ -13,6 +13,7 @@ use task_hookrs::uda::UDAValue;
 
 use chrono::{Local, NaiveDateTime, TimeZone};
 
+use crate::calendar::Calendar;
 use std::sync::{Arc, Mutex};
 use std::{sync::mpsc, thread, time::Duration};
 use tui::{
@@ -111,14 +112,15 @@ fn centered_rect(percent_x: u16, percent_y: u16, r: Rect) -> Rect {
 }
 
 pub enum AppMode {
-    Report,
-    Filter,
-    AddTask,
-    AnnotateTask,
-    LogTask,
-    ModifyTask,
-    HelpPopup,
+    TaskReport,
+    TaskFilter,
+    TaskAdd,
+    TaskAnnotate,
+    TaskLog,
+    TaskModify,
+    TaskHelpPopup,
     TaskError,
+    Calendar,
 }
 
 pub struct TTApp {
@@ -153,7 +155,7 @@ impl TTApp {
             command: "".to_string(),
             modify: "".to_string(),
             error: "".to_string(),
-            mode: AppMode::Report,
+            mode: AppMode::TaskReport,
             colors: TColorConfig::default(),
         };
         app.get_context();
@@ -186,6 +188,32 @@ impl TTApp {
     }
 
     pub fn draw(&mut self, f: &mut Frame<impl Backend>) {
+        match self.mode {
+            AppMode::TaskReport
+            | AppMode::TaskFilter
+            | AppMode::TaskAdd
+            | AppMode::TaskAnnotate
+            | AppMode::TaskError
+            | AppMode::TaskHelpPopup
+            | AppMode::TaskLog
+            | AppMode::TaskModify => self.draw_task(f),
+            AppMode::Calendar => self.draw_calendar(f),
+        }
+    }
+
+    pub fn draw_calendar(&mut self, f: &mut Frame<impl Backend>) {
+        let rects = Layout::default()
+            .direction(Direction::Vertical)
+            .constraints([Constraint::Min(0)].as_ref())
+            .split(f.size());
+        let c = &Calendar::new(2020).to_string()[..];
+        let p = Paragraph::new(Text::from(c))
+            .alignment(Alignment::Left)
+            .block(Block::default().borders(Borders::ALL).title("Calendar"));
+        f.render_widget(p, rects[0]);
+    }
+
+    pub fn draw_task(&mut self, f: &mut Frame<impl Backend>) {
         let tasks_is_empty = self.tasks.lock().unwrap().is_empty();
         let tasks_len = self.tasks.lock().unwrap().len();
         while !tasks_is_empty && self.state.selected().unwrap_or_default() >= tasks_len {
@@ -210,13 +238,13 @@ impl TTApp {
                 .unwrap_or_default()
         };
         match self.mode {
-            AppMode::Report => self.draw_command(f, rects[1], &self.filter[..], "Filter Tasks"),
-            AppMode::Filter => {
+            AppMode::TaskReport => self.draw_command(f, rects[1], &self.filter[..], "Filter Tasks"),
+            AppMode::TaskFilter => {
                 f.render_widget(Clear, rects[1]);
                 f.set_cursor(rects[1].x + self.cursor_location as u16 + 1, rects[1].y + 1);
                 self.draw_command(f, rects[1], &self.filter[..], "Filter Tasks");
             }
-            AppMode::ModifyTask => {
+            AppMode::TaskModify => {
                 f.set_cursor(rects[1].x + self.cursor_location as u16 + 1, rects[1].y + 1);
                 f.render_widget(Clear, rects[1]);
                 self.draw_command(
@@ -226,12 +254,12 @@ impl TTApp {
                     format!("Modify Task {}", task_id).as_str(),
                 );
             }
-            AppMode::LogTask => {
+            AppMode::TaskLog => {
                 f.set_cursor(rects[1].x + self.cursor_location as u16 + 1, rects[1].y + 1);
                 f.render_widget(Clear, rects[1]);
                 self.draw_command(f, rects[1], &self.command[..], "Log Task");
             }
-            AppMode::AnnotateTask => {
+            AppMode::TaskAnnotate => {
                 f.set_cursor(rects[1].x + self.cursor_location as u16 + 1, rects[1].y + 1);
                 f.render_widget(Clear, rects[1]);
                 self.draw_command(
@@ -241,7 +269,7 @@ impl TTApp {
                     format!("Annotate Task {}", task_id).as_str(),
                 );
             }
-            AppMode::AddTask => {
+            AppMode::TaskAdd => {
                 f.set_cursor(rects[1].x + self.cursor_location as u16 + 1, rects[1].y + 1);
                 f.render_widget(Clear, rects[1]);
                 self.draw_command(f, rects[1], &self.command[..], "Add Task");
@@ -250,10 +278,13 @@ impl TTApp {
                 f.render_widget(Clear, rects[1]);
                 self.draw_command(f, rects[1], &self.error[..], "Error");
             }
-            AppMode::HelpPopup => {
+            AppMode::TaskHelpPopup => {
                 self.draw_command(f, rects[1], &self.filter[..], "Filter Tasks");
                 self.draw_help_popup(f, f.size());
             }
+            _ => {
+                panic!("Reached unreachable code. Something went wrong");
+            }
         }
     }
 
@@ -546,12 +577,21 @@ impl TTApp {
         match attribute {
             "id" => task.id().unwrap_or_default().to_string(),
             "due" => match task.due() {
-                Some(v) => vague_format_date_time(Local::now().naive_utc(), NaiveDateTime::new(v.date(), v.time())),
+                Some(v) => vague_format_date_time(
+                    Local::now().naive_utc(),
+                    NaiveDateTime::new(v.date(), v.time()),
+                ),
                 None => "".to_string(),
             },
-            "entry" => vague_format_date_time(NaiveDateTime::new(task.entry().date(), task.entry().time()), Local::now().naive_utc()),
+            "entry" => vague_format_date_time(
+                NaiveDateTime::new(task.entry().date(), task.entry().time()),
+                Local::now().naive_utc(),
+            ),
             "start" => match task.start() {
-                Some(v) => vague_format_date_time(NaiveDateTime::new(v.date(), v.time()), Local::now().naive_utc()),
+                Some(v) => vague_format_date_time(
+                    NaiveDateTime::new(v.date(), v.time()),
+                    Local::now().naive_utc(),
+                ),
                 None => "".to_string(),
             },
             "description" => task.description().to_string(),
diff --git a/src/calendar.rs b/src/calendar.rs
new file mode 100644
index 0000000..5ffa51e
--- /dev/null
+++ b/src/calendar.rs
@@ -0,0 +1,206 @@
+// Based on https://play.rust-lang.org/?gist=1057364daeee4cff472a&version=nightly
+// See: https://old.reddit.com/r/rust/comments/37b6oo/the_calendar_example_challenge/crlmbsg/
+
+use std::fmt;
+
+const COL_WIDTH: usize = 21;
+
+use Day::*;
+use Month::*;
+
+#[derive(Clone, Copy, Debug)]
+#[repr(u8)]
+pub enum Day {
+    Sun,
+    Mon,
+    Tue,
+    Wed,
+    Thu,
+    Fri,
+    Sat,
+}
+
+#[derive(Clone, Copy, Debug, Eq, PartialEq)]
+pub enum Month {
+    Jan,
+    Feb,
+    Mar,
+    Apr,
+    May,
+    Jun,
+    Jul,
+    Aug,
+    Sep,
+    Oct,
+    Nov,
+    Dec,
+}
+impl Month {
+    fn len(self) -> u8 {
+        match self {
+            Jan => 31,
+            Feb => 28,
+            Mar => 31,
+            Apr => 30,
+            May => 31,
+            Jun => 30,
+            Jul => 31,
+            Aug => 31,
+            Sep => 30,
+            Oct => 31,
+            Nov => 30,
+            Dec => 31,
+        }
+    }
+    fn leap_len(self, leap_year: bool) -> u8 {
+        match self {
+            Feb => {
+                if leap_year {
+                    29
+                } else {
+                    28
+                }
+            }
+            mon => mon.len(),
+        }
+    }
+    fn first_day(self, year: i64) -> Day {
+        let y = year - 1;
+        let jan_first = (1 + (5 * (y % 4)) + (4 * (y % 100)) + (6 * (y % 400))) % 7;
+        let mut len = 0;
+        for m in Jan {
+            if m == self {
+                break;
+            }
+            len += m.leap_len(is_leap_year(year)) as i64;
+        }
+        match (len + jan_first) % 7 {
+            0 => Sun,
+            1 => Mon,
+            2 => Tue,
+            3 => Wed,
+            4 => Thu,
+            5 => Fri,
+            _ => Sat,
+        }
+    }
+}
+impl Iterator for Month {
+    type Item = Month;
+    fn next(&mut self) -> Option<Month> {
+        let ret = Some(*self);
+        *self = match *self {
+            Jan => Feb,
+            Feb => Mar,
+            Mar => Apr,
+            Apr => May,
+            May => Jun,
+            Jun => Jul,
+            Jul => Aug,
+            Aug => Sep,
+            Sep => Oct,
+            Oct => Nov,
+            Nov => Dec,
+            Dec => Jan,
+        };
+        ret
+    }
+}
+impl fmt::Display for Month {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        let name = match *self {
+            Jan => "January",
+            Feb => "February",
+            Mar => "March",
+            Apr => "April",
+            May => "May",
+            Jun => "June",
+            Jul => "July",
+            Aug => "August",
+            Sep => "September",
+            Oct => "October",
+            Nov => "November",
+            Dec => "December",
+        };
+        let padding = COL_WIDTH - name.len();
+        write!(f, "{:1$}", "", padding / 2)?;
+        if padding % 2 != 0 {
+            f.write_str(" ")?;
+        }
+        f.write_str(name)?;
+        write!(f, "{:1$}", "", padding / 2)
+    }
+}
+
+pub struct Calendar {
+    pub year: i64,
+}
+
+impl Calendar {
+    pub fn new(year: i64) -> Self {
+        Self { year }
+    }
+}
+
+fn is_leap_year(year: i64) -> bool {
+    (year % 4 == 0 && year % 100 != 0) || year % 400 == 0
+}
+
+impl fmt::Display for Calendar {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        let cols = f.width().unwrap_or(3);
+        let year = self.year;
+        let leap_year = is_leap_year(year);
+        let months = [Jan, Feb, Mar, Apr, May, Jun, Jul, Aug, Sep, Oct, Nov, Dec];
+        let mut dates = [
+            0..Jan.len(),
+            0..Feb.leap_len(leap_year),
+            0..Mar.len(),
+            0..Apr.len(),
+            0..May.len(),
+            0..Jun.len(),
+            0..Jul.len(),
+            0..Aug.len(),
+            0..Sep.len(),
+            0..Oct.len(),
+            0..Nov.len(),
+            0..Dec.len(),
+        ];
+        let chunks = dates.chunks_mut(cols).zip(months.chunks(cols));
+        for (days_chunk, months) in chunks {
+            for month in months {
+                write!(f, "{:>1$} ", month, COL_WIDTH)?;
+            }
+            f.write_str("\n")?;
+            for month in months {
+                write!(f, "{:>1$} ", " S  M  T  W  T  F  S", COL_WIDTH)?;
+            }
+            f.write_str("\n")?;
+            for (days, mon) in days_chunk.iter_mut().zip(months.iter()) {
+                let first_day = mon.first_day(year) as u8;
+                for _ in 0..(first_day) {
+                    f.write_str("   ")?;
+                }
+                for _ in 0..(7 - first_day) {
+                    write!(f, "{:>3}", days.next().unwrap() + 1)?;
+                }
+                f.write_str(" ")?;
+            }
+            f.write_str("\n")?;
+            while !days_chunk.iter().all(|r| r.start == r.end) {
+                for days in days_chunk.iter_mut() {
+                    for _ in 0..7 {
+                        match days.next() {
+                            Some(s) => write!(f, "{:>3}", s + 1)?,
+                            None => f.write_str("   ")?,
+                        }
+                    }
+                    f.write_str(" ")?;
+                }
+                f.write_str("\n")?;
+            }
+            f.write_str("\n")?;
+        }
+        Ok(())
+    }
+}
diff --git a/src/main.rs b/src/main.rs
index 6021b08..3c67c70 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -3,6 +3,7 @@
 #![allow(unused_variables)]
 
 mod app;
+mod calendar;
 mod color;
 mod util;
 
@@ -57,8 +58,11 @@ fn tui_main(_config: &str) -> Result<(), Box<dyn Error>> {
         // Handle input
         match events.next()? {
             Event::Input(input) => match app.mode {
-                AppMode::Report => match input {
+                AppMode::TaskReport => match input {
                     Key::Ctrl('c') | Key::Char('q') => app.should_quit = true,
+                    Key::Char(']') => {
+                        app.mode = AppMode::Calendar;
+                    }
                     Key::Char('r') => app.update(),
                     Key::Down | Key::Char('j') => app.next(),
                     Key::Up | Key::Char('k') => app.previous(),
@@ -103,7 +107,7 @@ fn tui_main(_config: &str) -> Result<(), Box<dyn Error>> {
                         }
                     }
                     Key::Char('m') => {
-                        app.mode = AppMode::ModifyTask;
+                        app.mode = AppMode::TaskModify;
                         match app.task_current() {
                             Some(t) => app.modify = t.description().to_string(),
                             None => app.modify = "".to_string(),
@@ -111,35 +115,35 @@ fn tui_main(_config: &str) -> Result<(), Box<dyn Error>> {
                         app.cursor_location = app.modify.chars().count();
                     }
                     Key::Char('l') => {
-                        app.mode = AppMode::LogTask;
+                        app.mode = AppMode::TaskLog;
                     }
                     Key::Char('a') => {
-                        app.mode = AppMode::AddTask;
+                        app.mode = AppMode::TaskAdd;
                         app.cursor_location = app.command.chars().count();
                     }
                     Key::Char('A') => {
-                        app.mode = AppMode::AnnotateTask;
+                        app.mode = AppMode::TaskAnnotate;
                         app.cursor_location = app.command.chars().count();
                     }
                     Key::Char('?') => {
-                        app.mode = AppMode::HelpPopup;
+                        app.mode = AppMode::TaskHelpPopup;
                     }
                     Key::Char('/') => {
-                        app.mode = AppMode::Filter;
+                        app.mode = AppMode::TaskFilter;
                         app.cursor_location = app.filter.chars().count();
                     }
                     _ => {}
                 },
-                AppMode::HelpPopup => match input {
+                AppMode::TaskHelpPopup => match input {
                     Key::Esc => {
-                        app.mode = AppMode::Report;
+                        app.mode = AppMode::TaskReport;
                     }
                     _ => {}
                 },
-                AppMode::ModifyTask => match input {
+                AppMode::TaskModify => match input {
                     Key::Char('\n') => match app.task_modify() {
                         Ok(_) => {
-                            app.mode = AppMode::Report;
+                            app.mode = AppMode::TaskReport;
                             app.update();
                         }
                         Err(e) => {
@@ -149,7 +153,7 @@ fn tui_main(_config: &str) -> Result<(), Box<dyn Error>> {
                     },
                     Key::Esc => {
                         app.modify = "".to_string();
-                        app.mode = AppMode::Report;
+                        app.mode = AppMode::TaskReport;
                     }
                     Key::Right => {
                         if app.cursor_location < app.modify.chars().count() {
@@ -179,10 +183,10 @@ fn tui_main(_config: &str) -> Result<(), Box<dyn Error>> {
                     }
                     _ => {}
                 },
-                AppMode::LogTask => match input {
+                AppMode::TaskLog => match input {
                     Key::Char('\n') => match app.task_log() {
                         Ok(_) => {
-                            app.mode = AppMode::Report;
+                            app.mode = AppMode::TaskReport;
                             app.update();
                         }
                         Err(e) => {
@@ -192,7 +196,7 @@ fn tui_main(_config: &str) -> Result<(), Box<dyn Error>> {
                     },
                     Key::Esc => {
                         app.command = "".to_string();
-                        app.mode = AppMode::Report;
+                        app.mode = AppMode::TaskReport;
                     }
                     Key::Right => {
                         if app.cursor_location < app.command.chars().count() {
@@ -222,10 +226,10 @@ fn tui_main(_config: &str) -> Result<(), Box<dyn Error>> {
                     }
                     _ => {}
                 },
-                AppMode::AnnotateTask => match input {
+                AppMode::TaskAnnotate => match input {
                     Key::Char('\n') => match app.task_annotate() {
                         Ok(_) => {
-                            app.mode = AppMode::Report;
+                            app.mode = AppMode::TaskReport;
                             app.update();
                         }
                         Err(e) => {
@@ -235,7 +239,7 @@ fn tui_main(_config: &str) -> Result<(), Box<dyn Error>> {
                     },
                     Key::Esc => {
                         app.command = "".to_string();
-                        app.mode = AppMode::Report;
+                        app.mode = AppMode::TaskReport;
                     }
                     Key::Right => {
                         if app.cursor_location < app.command.chars().count() {
@@ -265,10 +269,10 @@ fn tui_main(_config: &str) -> Result<(), Box<dyn Error>> {
                     }
                     _ => {}
                 },
-                AppMode::AddTask => match input {
+                AppMode::TaskAdd => match input {
                     Key::Char('\n') => match app.task_add() {
                         Ok(_) => {
-                            app.mode = AppMode::Report;
+                            app.mode = AppMode::TaskReport;
                             app.update();
                         }
                         Err(e) => {
@@ -278,7 +282,7 @@ fn tui_main(_config: &str) -> Result<(), Box<dyn Error>> {
                     },
                     Key::Esc => {
                         app.command = "".to_string();
-                        app.mode = AppMode::Report;
+                        app.mode = AppMode::TaskReport;
                     }
                     Key::Right => {
                         if app.cursor_location < app.command.chars().count() {
@@ -308,9 +312,9 @@ fn tui_main(_config: &str) -> Result<(), Box<dyn Error>> {
                     }
                     _ => {}
                 },
-                AppMode::Filter => match input {
+                AppMode::TaskFilter => match input {
                     Key::Char('\n') | Key::Esc => {
-                        app.mode = AppMode::Report;
+                        app.mode = AppMode::TaskReport;
                         app.update();
                     }
                     Key::Right => {
@@ -343,9 +347,16 @@ fn tui_main(_config: &str) -> Result<(), Box<dyn Error>> {
                 },
                 AppMode::TaskError => match input {
                     _ => {
-                        app.mode = AppMode::Report;
+                        app.mode = AppMode::TaskReport;
                     }
                 },
+                AppMode::Calendar => match input {
+                    Key::Char('[') => {
+                        app.mode = AppMode::TaskReport;
+                    }
+                    Key::Ctrl('c') | Key::Char('q') => app.should_quit = true,
+                    _ => {}
+                },
             },
             Event::Tick => app.update(),
         }
@@ -355,5 +366,6 @@ fn tui_main(_config: &str) -> Result<(), Box<dyn Error>> {
             break;
         }
     }
+
     Ok(())
 }