ERB Formatter Online

This ERB formatter analyzes templates containing HTML and Embedded Ruby. It identifies ERB blocks (<% ... %>, <%= ... %>, <%- ... -%>), HTML nodes, and text, then outputs a consistently indented version that preserves runtime semantics. It supports nested blocks, inline Ruby expressions, and common Rails patterns while maintaining the original HTML structure. The tool operates in an idempotent fashion, so repeated formatting yields the same result. It offers configurable indentation (2 or 4 spaces) and optional line-wrapping, enabling teams to enforce a unified style across views, mailers, and partials. By focusing on structural formatting rather than code execution, it provides a safe, revision-friendly formatting step for code reviews and CI pipelines. It is particularly valuable for Rails projects with large view hierarchies and contributions from multiple developers who must align on template aesthetics and readability. Core features include block-aware indentation, preservation of HTML attributes, handling of embedded Ruby in attributes, and diagnostics for potential syntax irregularities without executing the code. Use cases include standardizing Rails view templates, preparing views for pull requests, and integrating into pre-commit checks or CI pipelines for consistent formatting.