---
title: "Train Wi-Fi slow on Mac: test it, save data or use your hotspot · Kilobat Guides"
url: "https://kilobat.app/zh-hans/guides/train-wifi-mac"
description: "Train Wi-Fi is shared by many passengers and drops along the route. Test it, get more from it, and know when your phone's hotspot is the better choice."
---

# Mac 上的火车 Wi-Fi：让它能用，或改用你的热点

Train Wi-Fi usually reaches the internet over mobile networks along the track. All the passengers share that connection, so it is often slow.

Applies to: All current macOS versions. Instant Hotspot needs an iPhone or a cellular iPad with the same Apple Account as the Mac. · 核查日期：2026年10月29日

## 症状

- The Mac joins and signs in, but pages load slowly or not at all.
- Calls freeze and uploads stop.
- The connection drops in tunnels and between stations, then comes back.
- The sign-in page appears again after some time.

## 可能的原因

- **A shared connection.** The train's connection serves all its passengers. A full train leaves little speed for each device.
- **Gaps in mobile coverage.** Tunnels, cuttings and rural areas interrupt the mobile networks that the train uses.
- **Limits from the operator.** Some operators limit the speed, the data or the time for each device. Some block streaming.
- **The sign-in, a VPN or custom DNS.** Train Wi-Fi often has a sign-in page. A VPN or custom DNS can hide it, as on other public networks.
- **Background data on the Mac.** Sync, backups and updates use the same small connection as your work.

## 如何检查

1. In a browser, open http://captive.apple.com. If the operator's page opens, sign in.
2. Run Apple's speed test. Write down the result.

   ```
   networkQuality
   ```
3. 查看当前有哪些进程在使用网络。按 q 停止。

   ```
   nettop -P -d
   ```
4. Look at the mobile signal on your phone. Strong signal and few passengers can make the hotspot faster.

## 如何修复

1. Turn on Low Data Mode for the train network. Choose Apple menu > System Settings > Wi-Fi.
2. Click Details next to the train network. Turn on Low data mode. Click OK.
3. Pause sync, backups and updates until you are on a better network.
4. In calls, turn off your camera. Audio uses much less of the connection.
5. If the train Wi-Fi is too slow, click the Wi-Fi icon. Choose your iPhone under Personal Hotspot.
6. Run the same speed test on the hotspot. Keep the faster of the two.
7. To stop the Mac from going back to the train Wi-Fi, open its Details. Turn off Automatically join this network.
8. On the hotspot, pause the apps that use data in the background. See [Mac uses Personal Hotspot data in the background](https://kilobat.app/zh-hans/guides/hotspot-background-data).
9. In tunnels and remote areas, the hotspot can drop too. Save your work before them.

## 使用 Kilobat

1. Find which part is slow: Wi-Fi, the router, the internet, DNS or the sign-in page.

   ```
   kilobat diagnose
   ```
2. Check the sign-in page, and whether the network logged you out after an earlier sign-in.

   ```
   kilobat portal
   ```
3. Test the speed with a limit on the data that the test uses.

   ```
   kilobat speedtest --budget-mb 10
   ```
4. 查看每个 App 的实时上传和下载。按 q 停止。

   ```
   kilobat status --watch
   ```
5. Mark the train network as metered. Kilobat then treats it like a hotspot.

   ```
   kilobat networks cost metered
   ```
6. For travel data packs, see [Working from anywhere with a Mac: eSIMs, phone hotspots and making data last](https://kilobat.app/zh-hans/guides/work-from-anywhere-mac-mobile-data).

## 常见问题

**Is train Wi-Fi or my hotspot faster?**

It depends on the route, the time and your carrier. Test both with the same test, then keep the faster one.

**Does train Wi-Fi use my phone's data?**

No. Train Wi-Fi does not use your data plan. The Personal Hotspot does.

**Is train Wi-Fi safe for work?**

Pages with https hide their contents from the network. Turn on a VPN after you sign in, if your work needs one.

## 参考资料

- [Apple Developer 新闻：How to modernize your captive network（2020年6月22日）](https://developer.apple.com/news/?id=q78sq5rv)
- [Apple 支持：Mac 上的 Wi-Fi 设置](https://support.apple.com/guide/mac-help/wi-fi-settings-on-mac-mh11935/mac)
- [Apple 支持：连接到 iPhone 或 iPad 的个人热点](https://support.apple.com/en-us/111785)
- [Apple 支持：使用智能热点连接到个人热点](https://support.apple.com/en-us/109321)
- [Apple 开发者：NWPath isExpensive](https://developer.apple.com/documentation/network/nwpath/isexpensive)
- networkQuality(8) and nettop(1), man page installed with macOS 27.2

核查日期：2026 年 10 月 29 日。

## 相关指南

- [Mac 在后台消耗个人热点流量](https://kilobat.app/zh-hans/guides/hotspot-background-data): 连接手机热点的 Mac 即使你什么都不做，也可能消耗大量流量。
- [Mac 上不显示 iPhone 热点](https://kilobat.app/zh-hans/guides/instant-hotspot-not-showing): 通过智能热点，Mac 无需密码即可加入你的 iPhone 或 iPad 热点。
- [用 Mac 随处工作：eSIM、手机热点和延长流量使用时间](https://kilobat.app/zh-hans/guides/work-from-anywhere-mac-mobile-data): 使用移动数据的 Mac 可能在几天内用尽旅行流量包。
- [让 Mac 将网络视为按流量计费](https://kilobat.app/zh-hans/guides/metered-network-mac): macOS 会将某些连接标记为高成本，例如 iPhone 个人热点。
- [在 Mac 上使用低数据模式](https://kilobat.app/zh-hans/guides/low-data-mode-mac): 低数据模式让 macOS 和 App 在某个 Wi-Fi 网络上减少流量消耗。
- [Mac 上不显示 Wi-Fi 登录页面](https://kilobat.app/zh-hans/guides/captive-portal-not-appearing): 公共网络通常会拦截所有流量，直到你在登录页面上完成登录。
- [Mac 上视频通话卡顿或冻结](https://kilobat.app/zh-hans/guides/video-call-stutter-mac): 通话更需要稳定的延迟和稳定的上传，而不是高速度。