---
title: cf.timings.client_tcp_rtt_msec
description: The smoothed TCP round-trip time (RTT) between Cloudflare and the client in milliseconds.
image: https://developers.cloudflare.com/core-services-preview.png
---

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#  cf.timings.client\_tcp\_rtt\_msec 

`cf.timings.client_tcp_rtt_msec` ` Number ` 

The smoothed TCP round-trip time (RTT) between Cloudflare and the client in milliseconds.

This field is only populated for TCP (HTTP/1, HTTP/2) connections. For QUIC connections, the value is `0`.

Example value:

```
20
```

Example usage:

```
# Match requests over TCP where the RTT exceeds 200 mscf.timings.client_quic_rtt_msec > 200
```

Categories: 
* Request

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