Which runtimes are supported?

Nine: Node.js, Python, Go, Rust, Ruby, Java, Deno, Bun, and static Nginx. Each preset ships a sensible multi-stage layout — a `builder` stage that installs dependencies (and compiles where relevant) and a `final` stage that copies the build artefacts into a smaller runtime image.

What does the matching docker-compose.yml contain?

A single `app` service that builds from the current directory, maps the final-stage EXPOSE port to the host, applies the environment variables you entered, and adds a `healthcheck:` block if you enabled one. It is intentionally minimal — just enough for `docker compose up` to bring the service online without hand-writing the build context or port mapping.

Why does the healthcheck show up in both files?

The Dockerfile `HEALTHCHECK` directive is what the Docker daemon uses to mark the container unhealthy; the compose `healthcheck:` block does the same thing when the container is started via Compose. Keeping the command, interval, timeout, and retries identical in both places ensures the container is marked unhealthy the same way regardless of how it is run.

Is anything uploaded?

No. Stage configuration, environment variables, and the generated Dockerfile and compose file are all produced in your browser; nothing you enter is sent to a server.

Dockerfile Builder

Generate production-ready Dockerfiles with multi-stage builds, .dockerignore, and companion Compose — all in your browser.

Dockerfile Compose Run → Compose

Configuration

Select language, base image, and core build settings

Runtime

Base Image Version

Multi-Stage Build

Smaller final images

Add Healthcheck

Shell-form CMD

Quick insert RUN

Build Stages

Configure build and final image stages

builder

Intermediate

Base Image

Working Directory

COPY before RUN (one per line; use --from=stage src dest)

RUN Commands (one per line)

COPY after RUN (source after deps install)

final

Final

Base Image

Working Directory

COPY before RUN (one per line; use --from=stage src dest)

RUN Commands (one per line)

COPY after RUN (source after deps install)

EXPOSE Port

CMD

ENTRYPOINT (optional)

Run as Non-Root User

Alpine/Debian-aware (nodejs)

Environment

Build ARGs

Optional build-time args

LABELs

e.g. org.opencontainers.image.source

Best practices

Multi-stage keeps build tools out of the final image.
Non-root USER improves container security.
Dependency files are copied before source for better layer caching.

Generated Files

# Generated by DevTools Dockerfile Builder — https://www.devtools.tools/dockerfile-builder

# Build stage
FROM node:20-alpine AS builder

WORKDIR /app
COPY package*.json ./
RUN npm ci --omit=dev
COPY . .

# Runtime stage
FROM node:20-alpine

WORKDIR /app
COPY --from=builder /app/node_modules ./node_modules
COPY --from=builder /app/package*.json ./
COPY --from=builder /app .

ENV NODE_ENV=production

EXPOSE 3000

RUN addgroup -g 1001 -S nodejs && adduser -S nodejs -u 1001 -G nodejs
USER nodejs

CMD ["node", "server.js"]

About this tool

Generate production-ready Dockerfiles with multi-stage builds, healthchecks, non-root users and .dockerignore. Free online Dockerfile builder, no signup. Dockerfile Builder runs in the browser on DevTools. There is no signup, and your input stays on this device unless the tool explicitly performs a live network lookup.

What this tool does not do

Dockerfile Builder is a free in-browser utility, not a hosted API. It does not keep server-side history and is not a substitute for production verification in your own stack.

How do I use this tool?

How do I use Dockerfile Builder?
Open Dockerfile Builder, enter or paste your input, and copy the result. The page works without an account.

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