Get The Current DateTime With The TimeZone Offset In Rust

Introduction

I've got a bunch of posts about Rust's chrono. They've all led to this, which gets me what I'm looking for most of the time.

---
[dependencies]
chrono = "0.4.40"
---

use chrono::Local;

fn main() {
  let now = Local::now();
  println!("{}", now.to_rfc3339_opts(
    chrono::SecondsFormat::Secs, true)
  );
}

Output:

2025-04-23T23:48:21-04:00

I swear I all the posts and docs had me running around in circles with NaiveDateTime and TimeZone stuff. It's great if you need the complexity. But if I just want to do a date, this is it 99% of the time.

The Different Formats

The above example uses RFC 3339 which is like ISO 8601. The chrono::SecondsFormat::Secs stuff trims milliseconds. I don't need those most of the time. chrono will output RFC 3339 with the millisconds and RFC 2822 as well. Here's what all three built-in outputs look like:

---
[dependencies]
chrono = "0.4.40"
---

use chrono::Local;

fn main() {
  let now = Local::now();
  println!("{}", now.to_rfc2822());
  println!("{}", now.to_rfc3339());
  println!("{}", now.to_rfc3339_opts(
    chrono::SecondsFormat::Secs, true)
  );
}

Output:

Wed, 23 Apr 2025 23:48:21 -0400
2025-04-23T23:48:21.155232-04:00
2025-04-23T23:48:21-04:00

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