created_at2019-02-15 22:14:53.524274
updated_at2024-01-07 17:01:36.935656
descriptionLibrary for making SNTP requests
Vladimir Petrigo (vpetrigo)



sntpc test Build Status

Simple Rust SNTP client

This crate provides a method for sending requests to NTP servers and process responses, extracting received timestamp.

Supported SNTP protocol versions:



This crate works with Cargo and is on Add it to your Cargo.toml like so:

sntpc = "0.3.7"

By calling the get_time() method and providing a proper NTP pool or server you should get a valid synchronization timestamp:

use std::net::UdpSocket;
use std::time::Duration;

fn main() {
    let socket =
        UdpSocket::bind("").expect("Unable to create UDP socket");
       .expect("Unable to set UDP socket read timeout");
    let result =
        sntpc::simple_get_time("", socket);

    match result {
       Ok(time) => {
           let microseconds = sntpc::fraction_to_microseconds(time.sec_fraction());
           println!("Got time: {}.{}", time.sec(), microseconds);
       Err(err) => println!("Err: {:?}", err),

no_std support

Currently, there are basic no_std support available, thanks to no-std-net crate. There is an example available on how to use smoltcp stack and that should provide general idea on how to bootstrap no_std networking and timestamping tools for sntpc library usage

async support

Feature async_tokio allows to use crate together with tokio. There is an example: examples/

There is also no_std support with feature async, but it requires Rust >= 1.75-nightly version. The example can be found in separate repository.


You can find several examples that shows how to use the library in details under [examples/] folder. Currently, there are examples that show:

  • usage of SNTP library in std environment
  • usage of SNTP library with smoltcp TCP/IP stack. Some std dependencies required only due to smoltcp available interfaces


Contributions are always welcome! If you have an idea, it's best to float it by me before working on it to ensure no effort is wasted. If there's already an open issue for it, knock yourself out. See the contributing section for additional details


  1. Frank A. Stevenson: for implementing stricter adherence to RFC4330 verification scheme
  2. Timothy Mertz: for fixing possible overflow in offset calculation
  3. HannesH: for fixing a typo in the
  4. Richard Penney: for adding two indicators of the NTP server's accuracy into the NtpResult structure
  5. Vitali Pikulik: for adding async support

Really appreciate all your efforts! Please let me know if I forgot someone.


This project is licensed under:

Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in time by you, as defined in the 3-Clause BSD license, shall be licensed as above, without any additional terms or conditions.

Commit count: 191

cargo fmt