TL;DR: Yes, Twilio Segment can be used with visitors in mainland China, but reliability is inconsistent unless you plan for China’s network conditions and third-party dependencies. Segment’s web library (analytics.js) loads from cdn.segment.com and sends events to api.segment.io by default. You can proxy both through your own domain and CDN, but third-party SDKs still load from their partner CDNs and may remain slow or intermittent in China. Chinafy can improve website performance in China by detecting and handling slow or blocked resources and serving a synchronized, China-optimized version of your pages to audiences in China.

What is Twilio Segment?

Twilio Segment is a customer data platform (CDP) that collects events from web/mobile/server sources and routes them to warehouses and hundreds of downstream tools. For websites, Segment uses analytics.js to load settings and destination bundles from its web library and to send tracking calls.

Does Segment work in mainland China?

Technically yes, but websites using Segment often struggle for a few reasons. Segment endpoints aren’t “blocked” in mainland China in the categorical sense, but performance varies because most assets live outside mainland China and many pages that use Segment also reference third-party resources that are slow or fail under China’s cross-border constraints. In practice, website visitors may see late or missing analytics calls, delayed destination loads, or other script-caused stalls.

Why Segment-embedded pages struggle in China

Cross-border latency: Default analytics.js and API endpoints (cdn.segment.com, api.segment.io) are fetched across limited international links, adding RTT and packet loss risk. The effects of location and distance are emphasized and more extreme than other markets given China’s internet ecosystem infrastructure , leading to higher latency than the same distance for other countries.

Third-party destination SDKs: Even if you proxy Analytics.js through your own domain/CDN (content delivery network), third-party SDKs still come from partner CDNs, so any China-incompatible third parties can continue to stall loads.

Scripts & dependencies: Separately to Segment assets, web pages generally include external fonts, trackers, and widgets that are slow or blocked in China, which a CDN alone won’t remediate.

How to make Segment work in China

To make any website work in China, there are two key components to consider: its infrastructure and its code.

On the infrastructure side, Segment has docs available for supporting customer-managed proxies. This offers Segment users the ability to serve analytics.js and send tracking calls via their own host and CDN (content delivery network), which enables greater control over where your website’s assets are delivered from. However, third-party SDKs still load from partners’ CDNs and aren’t able to be proxied.

Similarly, a near-China or China-based CDN for your website can improve loading speeds as static assets will be delivered from a node closer to the end user. However, as is the case with onshore hosting, a China CDN only solves part of the problem with cross-border China web performance. A CDN, no matter the locations of its Points of Presence (PoPs), does not handle third-party resources on the code-based side, which are often the primary technical reason why websites perform poorly in mainland China.

Chinafy offers a solution to make your existing website work faster and fuller in mainland China,

Here’s how Chinafy works:

Generates a version of your website for China visitors without affecting your current site.

Combines both in-person and platform-level features to detect and replace blocked or slow resources that cause loading delays.

If you're hosting offshore, Chinafy routes China-IP-based traffic to the China-optimized version of your site. If you're already hosting onshore, all your traffic will see the optimized version for China visitors.

Chinafy then keeps your China-optimized site in sync with your global one, so any content changes are reflected accordingly.

Note: Chinafy does not work with websites that are officially blocked or inaccessible in China.

How to check your web pages from China

You can use Chinafy’s Global Speed Test and Visual Speed Test to test any representative page (for example, with analytics.js web library assets). Compare Beijing/Shanghai/Guangzhou metrics with your global baseline to see both time‑to‑first‑byte and page‑complete behavior.

When you need an ICP license

Businesses differ in terms of its requirements when operating or marketing to Mainland China, with variables including industry, information collection and more. Specific to hosting in China, an ICP filing or license is legally required if you host or use any servers inside of mainland China or use a China-based CDN. This requirement applies to any website that is physically hosted within China or utilizes China-based infrastructure - regardless of the marketing tech stack being used.

Twilio Segment itself can be accessed from China, but what determines real-world reliability is the page around Segment, including third-party resources, like fonts, images and trackers. Some may opt for a CDN or proxy to try and improve routing for analytics.js and API calls, and to address both infrastructure-based and code-based incompatibilities, use Chinafy to remediate both issues so pages load fast and fully.

If you’re looking for ways to make your Segment-powered website or landing pages work in mainland China, contact Chinafy for a website evaluation.