EJS (Embedded JavaScript Templates)
Embedded JavaScript templating for Node.js and browsers. EJS uses <% %> tags to embed JavaScript directly in templates — full JavaScript power without a custom DSL. The default view engine for Express.js. Simpler to learn than Handlebars or Nunjucks for developers who prefer writing JavaScript in templates rather than learning template-specific syntax.
Score Breakdown
⚙ Agent Friendliness
🔒 Security
XSS risk with <%- %> unescaped output. Full JavaScript in templates enables arbitrary code execution — never execute user-supplied EJS templates. Keep auto-escaping <%= %> for all user data.
⚡ Reliability
Best When
Building Express.js apps where developers prefer writing JavaScript in templates and template inheritance isn't needed.
Avoid When
You need template inheritance, strict logic-template separation, or you want a safer templating surface with limited JavaScript access.
Use Cases
- • Render dynamic HTML in Express.js agent web applications using EJS as the view engine with res.render('template', data)
- • Generate server-side HTML pages with dynamic agent data using EJS's full JavaScript access for conditionals, loops, and formatting
- • Produce text-based output (emails, config files, code) from templates where EJS's embedded JavaScript enables complex generation logic
- • Build agent report templates where team members familiar with JavaScript can maintain templates without learning a custom DSL
- • Create simple HTML templates for agent notification emails using EJS's straightforward include() partial system
Not For
- • Complex template inheritance — EJS has no native template inheritance (extends/block); use Nunjucks or Handlebars for base/child template patterns
- • Large codebases where template logic separation is important — EJS's full JavaScript access encourages mixing logic with presentation
- • Front-end component rendering — EJS is for server-side HTML generation; use React/Vue for interactive client-side rendering
Interface
Authentication
No authentication — local templating library.
Pricing
EJS is open source and free.
Agent Metadata
Known Gotchas
- ⚠ EJS auto-escapes <%= output %> but not <%- raw_output %> — use <%- %> only for trusted HTML; user data in <%- %> is an XSS vulnerability
- ⚠ Full JavaScript access in templates means template logic creep is common — the same reason EJS is easy is why it becomes hard to maintain at scale
- ⚠ Template caching is off by default — enable {cache: true} in production to avoid repeated template compilation on each request
- ⚠ EJS partials use <%- include('partial', {data}) %> syntax with data passing — forgetting to pass data to partials results in undefined variables in included templates
- ⚠ Error stack traces in EJS point to compiled JS, not the .ejs template — the filename/line in errors may not directly map to template file lines
- ⚠ EJS 3.x is not a breaking change from 2.x but some edge cases with whitespace trimming changed — test template output after upgrading
Alternatives
Full Evaluation Report
Detailed scoring breakdown, competitive positioning, security analysis, and improvement recommendations for EJS (Embedded JavaScript Templates).
Scores are editorial opinions as of 2026-03-06.