diff --git a/.gitignore b/.gitignore
index 87270ee..086183e 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,2 +1,3 @@
 /target
 result/
+*.json
diff --git a/Cargo.lock b/Cargo.lock
index 0991c97..e096f7e 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -193,6 +193,9 @@ name = "bitflags"
 version = "2.6.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "b048fb63fd8b5923fc5aa7b340d8e156aec7ec02f0c78fa8a6ddc2613f6f71de"
+dependencies = [
+ "serde",
+]
 
 [[package]]
 name = "block-buffer"
@@ -428,6 +431,7 @@ dependencies = [
  "mio",
  "parking_lot",
  "rustix",
+ "serde",
  "signal-hook",
  "signal-hook-mio",
  "winapi",
@@ -1441,9 +1445,9 @@ dependencies = [
 
 [[package]]
 name = "serde_json"
-version = "1.0.132"
+version = "1.0.133"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "d726bfaff4b320266d395898905d0eba0345aae23b54aee3a737e260fd46db03"
+checksum = "c7fceb2473b9166b2294ef05efcb65a3db80803f0b03ef86a5fc88a2b85ee377"
 dependencies = [
  "itoa",
  "memchr",
@@ -1484,6 +1488,7 @@ dependencies = [
  "futures",
  "ironcalc",
  "ratatui",
+ "serde_json",
  "slice-utils",
  "thiserror",
  "tui-popup",
diff --git a/Cargo.toml b/Cargo.toml
index 426a38b..d337a2a 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -8,7 +8,7 @@ edition = "2021"
 [dependencies]
 anyhow = { version = "1.0.91", features = ["backtrace"] }
 clap = { version = "4.5.20", features = ["derive"] }
-crossterm = { version = "0.28.1", features = ["event-stream"] }
+crossterm = { version = "0.28.1", features = ["event-stream", "serde"] }
 csvx = "0.1.17"
 ironcalc = { git = "https://github.com/ironcalc/IronCalc" }
 futures = "0.3.31"
@@ -18,3 +18,4 @@ tui-textarea = "0.7.0"
 tui-prompts = "0.5.0"
 slice-utils = { git = "https://dev.zaphar.net/zaphar/slice-cursor-rs.git", ref = "main" }
 tui-popup = "0.6.0"
+serde_json = "1.0.133"
diff --git a/src/main.rs b/src/main.rs
index 200e3c6..cd6b9ac 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -3,6 +3,9 @@ use std::{path::PathBuf, process::ExitCode};
 use clap::Parser;
 use crossterm::event;
 use ratatui;
+use serde_json::to_writer;
+use std::io::Write;
+
 use ui::Workspace;
 
 mod book;
@@ -17,14 +20,33 @@ pub struct Args {
     locale_name: String,
     #[arg(default_value_t=String::from("America/New_York"), short, long)]
     timezone_name: String,
+    #[arg(long)]
+    log_input: Option<PathBuf>,
 }
 
+type ReadFn = Box<dyn FnMut() -> anyhow::Result<event::Event>>;
+
 fn run(terminal: &mut ratatui::DefaultTerminal, args: Args) -> anyhow::Result<ExitCode> {
     let mut ws = Workspace::load(&args.workbook, &args.locale_name, &args.timezone_name)?;
-
+    let mut read_func: ReadFn = if let Some(log_path) = args.log_input {
+        {
+            let log_file = std::fs::File::create(log_path)?;
+            Box::new(move || {
+                let evt = event::read()?;
+                to_writer(&log_file, &evt)?;
+                writeln!(&log_file, "")?;
+                Ok(evt)
+            })
+        }
+    } else {
+        Box::new(|| {
+            let evt = event::read()?;
+            Ok(evt)
+        })
+    };
     loop {
         terminal.draw(|frame| ui::render::draw(frame, &mut ws))?;
-        if let Some(code) = ws.handle_input(event::read()?)? {
+        if let Some(code) = ws.handle_input(read_func()?)? {
             return Ok(code);
         }
     }