IMG

Docker Image Size Calculator

Estimate the real download size of an image, layer by layer, or analyze a Dockerfile for security and optimization issues — before docker pull or docker build.

layers
size
multi-arch
Dockerfile lint

Waiting to check...

image reference

Image name

Dockerfile

Waiting for input...

Input Dockerfile

Analysis result

—Stages

—Layer instruction

—Errors

—Warnings

The "Registry" check runs from the Backserver server, calling the Docker Registry HTTP API v2 directly (no Docker install needed); its numbers are the compressed, downloadable size, not the final on-disk size. Compatible public registries (Docker Hub, GHCR, Quay, GCR) are supported, and connections to internal addresses are blocked. The "Dockerfile analysis" section runs entirely in your browser; your file is never sent anywhere unless you explicitly click "Get base image size" for the final stage. This analysis is based on common Docker security and optimization rules, not a real build — the true final size can only be determined by running docker build.