---
title: ClientInfo
summary: Information about the downstream client making the request to the Fastly Compute service.
url: https://www.fastly.com/documentation/reference/compute/sdks/javascript/js-compute/globals/interface.ClientInfo/
---

**Kind:** Interface  
**Module:** [globals](https://www.fastly.com/documentation/reference/compute/sdks/javascript/js-compute/globals/)  
**Package:** @fastly/js-compute 4.0.1  
**Source:** https://github.com/fastly/js-compute-runtime/blob/70cf30af4e657879b2d1e7eafab880e39e3a3f7d/types/globals.d.ts#L455

Information about the downstream client making the request to the Fastly Compute service.

## Properties

### requestId

**Type:** `string`  
**Flags:** read-only, since 3.40.1  
**Source:** https://github.com/fastly/js-compute-runtime/blob/70cf30af4e657879b2d1e7eafab880e39e3a3f7d/types/globals.d.ts#L460

A UUID generated by Fastly Compute for each request.

### address

**Type:** `string`  
**Flags:** read-only  
**Source:** https://github.com/fastly/js-compute-runtime/blob/70cf30af4e657879b2d1e7eafab880e39e3a3f7d/types/globals.d.ts#L464

A string representation of the IPv4 or IPv6 address of the downstream client.

### geo

**Type:** `Geolocation | null`  
**Flags:** read-only  
**Source:** https://github.com/fastly/js-compute-runtime/blob/70cf30af4e657879b2d1e7eafab880e39e3a3f7d/types/globals.d.ts#L468

Geolocation data for the client IP address, or `null` if unavailable.

### tlsJA3MD5

**Type:** `string | null`  
**Flags:** read-only, since 3.2.1  
**Source:** https://github.com/fastly/js-compute-runtime/blob/70cf30af4e657879b2d1e7eafab880e39e3a3f7d/types/globals.d.ts#L473

The JA3 hash of the TLS ClientHello message, or `null` if unavailable.

### tlsJA4

**Type:** `string | null`  
**Flags:** read-only, since 3.37.0  
**Source:** https://github.com/fastly/js-compute-runtime/blob/70cf30af4e657879b2d1e7eafab880e39e3a3f7d/types/globals.d.ts#L478

The JA4 fingerprint of the TLS ClientHello message, or `null` if unavailable.

### h2Fingerprint

**Type:** `string | null`  
**Flags:** read-only, since 3.37.0  
**Source:** https://github.com/fastly/js-compute-runtime/blob/70cf30af4e657879b2d1e7eafab880e39e3a3f7d/types/globals.d.ts#L484

The HTTP/2 fingerprint for HTTP/2 connections, or `null` for HTTP/1.1
connections or when unavailable.

### ohFingerprint

**Type:** `string | null`  
**Flags:** read-only, since 3.37.0  
**Source:** https://github.com/fastly/js-compute-runtime/blob/70cf30af4e657879b2d1e7eafab880e39e3a3f7d/types/globals.d.ts#L490

The Original Header fingerprint based on the order and presence of request
headers, or `null` if unavailable.

### tlsCipherOpensslName

**Type:** `string | null`  
**Flags:** read-only, since 3.2.1  
**Source:** https://github.com/fastly/js-compute-runtime/blob/70cf30af4e657879b2d1e7eafab880e39e3a3f7d/types/globals.d.ts#L496

The cipher suite used to secure the client TLS connection, or `null` if
unavailable.

### tlsProtocol

**Type:** `string | null`  
**Flags:** read-only, since 3.2.1  
**Source:** https://github.com/fastly/js-compute-runtime/blob/70cf30af4e657879b2d1e7eafab880e39e3a3f7d/types/globals.d.ts#L502

The TLS protocol version used to secure the client TLS connection, or
`null` if unavailable.

### tlsClientCertificate

**Type:** `ArrayBuffer | null`  
**Flags:** read-only, since 3.2.1  
**Source:** https://github.com/fastly/js-compute-runtime/blob/70cf30af4e657879b2d1e7eafab880e39e3a3f7d/types/globals.d.ts#L509

The raw client certificate from the mutual TLS handshake in PEM format,
or `null` if unavailable. Returns an empty `ArrayBuffer` if the connection
is not mTLS.

### tlsClientHello

**Type:** `ArrayBuffer | null`  
**Flags:** read-only, since 3.2.1  
**Source:** https://github.com/fastly/js-compute-runtime/blob/70cf30af4e657879b2d1e7eafab880e39e3a3f7d/types/globals.d.ts#L515

The raw bytes sent by the client in the TLS ClientHello message, or
`null` if unavailable.

### tlsClientSNI

**Type:** `string | null`  
**Flags:** read-only, since 3.45.0  
**Source:** https://github.com/fastly/js-compute-runtime/blob/70cf30af4e657879b2d1e7eafab880e39e3a3f7d/types/globals.d.ts#L520

The raw Server Name Indication (SNI) the client sent in the ClientHello TLS record.