Does this send my code to a server?

No. The entire generator runs in your browser — no data is sent to any server at any point.

What is a multi-stage build and when is it used?

A multi-stage build uses multiple FROM instructions in one Dockerfile. The first stage compiles or builds the app; the second copies only the output into a smaller base image, reducing final image size. It is enabled automatically for Go and Java stacks.

Which base image should I choose?

Alpine images are the smallest but can have glibc compatibility issues. Slim (Debian-based) images are a good balance. Use the full image when you need system libraries that Alpine omits.

Can I add multiple environment variables?

Yes. Enter one KEY=VALUE pair per line in the environment variables field. Lines that are blank or do not contain "=" are ignored.

Is the generated Dockerfile production-ready?

It follows common best practices — layer caching, .dockerignore hints, non-root user for Node/Python, and multi-stage builds for compiled languages. Review and adjust it for your specific security and performance requirements before deploying.

Dockerfile Generator

Pick a language stack, configure your options, and get a production-ready Dockerfile in seconds.

Configuration

Language / Stack

Base Image Variant

Exposed Port

Start Command

Working Directory

Environment Variables (one KEY=VALUE per line)

Run as non-root user Show .dockerignore template

Dockerfile

Click "Generate Dockerfile" to see the output here.

Copied!

Summary

The Dockerfile Generator creates a ready-to-use Dockerfile for the most popular application stacks. Choose a language, select a base image variant, configure your exposed port and entry command, and optionally add environment variables. The output follows Docker best practices: non-root user, layer caching, minimal final image. Copy the result with one click or download it directly.

How it works

Select your application language from the stack dropdown.
Choose a base image variant (e.g. slim, alpine, LTS).
Enter the application port and the start command.
Optionally add environment variables as KEY=VALUE pairs.
Click "Generate Dockerfile" to produce the output.
Copy or download the generated Dockerfile.

Use cases

Bootstrap a Dockerfile for a new Node.js or Python project.
Quickly containerize an existing app without memorizing Dockerfile syntax.
Generate a multi-stage build template for Go or Java.
Create a PHP-FPM Dockerfile for use with an Nginx sidecar.
Experiment with different base image variants to compare image sizes.
Onboard junior developers to Docker best practices via generated examples.
Prototype CI/CD pipelines that need a working Dockerfile as starting point.
Teach containerization concepts in workshops or tutorials.

Frequently Asked Questions

Last updated: 2026-05-29 · Reviewed by Nham Vu