Docker for Selenium Grid: Complete 2026 Setup Guide

Last updated: June 29, 2026 · Reading time: 9 minutes · By SoftwareTestPilot Editorial Team

What you'll build: A production-ready Selenium 4 Grid in Docker — hub + Chrome + Firefox nodes via Docker Compose, dynamic scaling, video recording, GitHub Actions integration, and Kubernetes manifests for hundreds of parallel sessions.

• Consistent environment — same OS, browsers, drivers across dev/CI/prod
• Easy parallel execution — 10+ browser instances on one machine
• Scalable — Kubernetes for hundreds of parallel sessions
• Reproducible — versioned images for browser/driver combinations

For broader Selenium context, pair this with our Selenium WebDriver Guide, the GitHub Actions Selenium CI setup, and the CI/CD Pipeline Testing Tutorial.

• Docker Desktop or Docker Engine installed
• Docker Compose v2+
• 4 GB RAM minimum (8 GB+ for production)
• Selenium 4 Java/Python project

Create docker-compose.yml:

version: '3.8'
services:
  selenium-hub:
    image: selenium/hub:4.25
    ports:
      - "4442:4442"
      - "4443:4443"
      - "4444:4444"
    environment:
      - SE_EVENT_BUS_HOST=selenium-hub
      - SE_EVENT_BUS_PORT=4443

  chrome:
    image: selenium/node-chrome:4.25
    depends_on:
      - selenium-hub
    shm_size: 2gb
    environment:
      - SE_EVENT_BUS_HOST=selenium-hub
      - SE_EVENT_BUS_SUBSCRIBE_PORT=4443
      - SE_NODE_HOST=chrome
      - SE_NODE_PORT=5555

  firefox:
    image: selenium/node-firefox:4.25
    depends_on:
      - selenium-hub
    shm_size: 2gb
    environment:
      - SE_EVENT_BUS_HOST=selenium-hub
      - SE_EVENT_BUS_SUBSCRIBE_PORT=4443
      - SE_NODE_HOST=firefox
      - SE_NODE_PORT=5555

docker-compose up -d

Verify it's running:

curl http://localhost:4444/status

Should return {"value":{"ready":true,"message":"Selenium Grid ready...","nodes":[...]}}.

ChromeOptions options = new ChromeOptions();
options.addArguments("--headless=new");

WebDriver driver = new RemoteWebDriver(
    new URL("http://localhost:4444/wd/hub"),
    options
);

from selenium import webdriver
from selenium.webdriver.chrome.options import Options

options = Options()
options.add_argument("--headless=new")

driver = webdriver.Remote(
    command_executor="http://localhost:4444/wd/hub",
    options=options
)

For Java setup, see our Java for Selenium tutorial; for Python, the Selenium Python Q&A.

Add more nodes:

chrome-2:
  image: selenium/node-chrome:4.25
  depends_on:
    - selenium-hub
  shm_size: 2gb
  environment:
    - SE_EVENT_BUS_HOST=selenium-hub
    - SE_EVENT_BUS_SUBSCRIBE_PORT=4443

chrome-3:
  image: selenium/node-chrome:4.25
  depends_on:
    - selenium-hub
  shm_size: 2gb
  environment:
    - SE_EVENT_BUS_HOST=selenium-hub
    - SE_EVENT_BUS_SUBSCRIBE_PORT=4443

Or scale dynamically:

docker-compose up -d --scale chrome=5

Now you have 5 Chrome nodes.

Open http://localhost:4444 in your browser. You'll see:

• Active sessions
• Node capacity
• Queued requests

chrome:
  image: selenium/node-chrome:4.25
  shm_size: 2gb
  environment:
    - SE_EVENT_BUS_HOST=selenium-hub
    - SE_EVENT_BUS_SUBSCRIBE_PORT=4443
    - SE_ENABLE_TRACING=true
  volumes:
    - ./videos:/opt/selenium/videos

Videos saved to ./videos for debugging.

GitHub Actions

name: Selenium Grid Tests

on: [push, pull_request]

jobs:
  test:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4
      - uses: actions/setup-java@v4
        with: { distribution: temurin, java-version: '17' }

      - name: Start Selenium Grid
        run: docker-compose up -d

      - name: Wait for Grid
        run: |
          until curl -sf http://localhost:4444/status; do
            echo "Waiting for grid..."
            sleep 5
          done

      - name: Run Tests
        run: mvn test

      - name: Stop Grid
        if: always()
        run: docker-compose down

For production-scale Selenium Grid:

# selenium-hub.yaml
apiVersion: apps/v1
kind: Deployment
metadata:
  name: selenium-hub
spec:
  replicas: 1
  selector:
    matchLabels:
      app: selenium-hub
  template:
    metadata:
      labels:
        app: selenium-hub
    spec:
      containers:
      - name: hub
        image: selenium/hub:4.25
        ports:
        - containerPort: 4442
        - containerPort: 4443
        - containerPort: 4444

---
apiVersion: v1
kind: Service
metadata:
  name: selenium-hub
spec:
  selector:
    app: selenium-hub
  ports:
  - port: 4444
    targetPort: 4444

# selenium-node.yaml
apiVersion: apps/v1
kind: Deployment
metadata:
  name: selenium-node-chrome
spec:
  replicas: 5
  selector:
    matchLabels:
      app: selenium-node
  template:
    metadata:
      labels:
        app: selenium-node
    spec:
      containers:
      - name: chrome
        image: selenium/node-chrome:4.25
        env:
        - name: SE_EVENT_BUS_HOST
          value: selenium-hub
        - name: SE_EVENT_BUS_SUBSCRIBE_PORT
          value: "4443"

Do

• Use named volumes for video/screenshot persistence
• Set memory limits (mem_limit: 2g)
• Use --scale for dynamic node count
• Run in headless mode in CI
• Set retry policy for flaky tests

Don't

• Don't run too many nodes on one machine (memory limits)
• Don't run in non-headless mode in CI
• Don't expose the grid publicly without authentication
• Don't ignore resource limits

"No route to host"

Fix: Ensure all nodes can reach the hub. Check SE_EVENT_BUS_HOST.

"Session not created"

Fix: Browser/driver version mismatch. Use the same Selenium version for hub and nodes.

Out of memory

Fix: Reduce number of parallel sessions per node, or increase host memory.

Pattern 1 — Multi-arch builds

Build images for both ARM64 (Apple Silicon) and AMD64:

FROM --platform=$BUILDPLATFORM selenium/node-chrome:4.25
# ...

Use docker buildx for multi-arch builds.

Pattern 2 — Health checks

chrome:
  image: selenium/node-chrome:4.25
  healthcheck:
    test: ["CMD", "curl", "-f", "http://localhost:5555/status"]
    interval: 30s
    timeout: 10s
    retries: 3

Pattern 3 — Resource limits

chrome:
  image: selenium/node-chrome:4.25
  deploy:
    resources:
      limits:
        cpus: '1.0'
        memory: 1G
      reservations:
        cpus: '0.5'
        memory: 512M

Pattern 4 — Secrets management

secrets:
  - browserstack_key

services:
  chrome:
    image: selenium/node-chrome:4.25
    secrets:
      - browserstack_key

Pattern 5 — Health monitoring

prometheus:
  image: prom/prometheus
  volumes:
    - ./prometheus.yml:/etc/prometheus/prometheus.yml
  ports:
    - "9090:9090"

• Selenium WebDriver Guide
• GitHub Actions Selenium CI
• CI/CD Pipeline Testing Tutorial
• Selenium Python Interview Q&A
• SDET Career Roadmap

Official reference: SeleniumHQ/docker-selenium on GitHub.

Original SoftwareTestPilot research you can cite in reviews, RFCs, and interviews:

• TDD impact benchmarks (2026) — defect density, MTTD, PR test ratio.
• Test pyramid benchmarks (2026) — real 62 / 26 / 12 ratios and flake per layer.
• Shift-left benchmarks (2026) — DORA-style metrics and defect-fix cost.
• Enterprise automation tool benchmarks (2026) — flake vs licence cost.
• Selenium market benchmarks (2026) and Playwright market benchmarks (2026).