Jinja Renderer
Renders a Jinja-style template against local JSON data. Supports a documented subset: variables,
dotted paths, filters, if/elif/else, and for loops.
There is no code execution, no eval, and no macros/include/extends.
Private by architecture:
All processing is 100% client-side memory. Your data never leaves this browser tab.
Template
0 lines · 0 charsTemplate (Jinja subset)
JSON data
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Rendered output
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About This Tool
Renders a documented subset of Jinja2 template syntax (variables, dotted paths, filters, if/elif/else branching, and for loops) against a JSON object you supply, running entirely in a client-side hand-written interpreter.
Useful for previewing transactional email templates, configuration manifests, and dynamic HTML components without setting up a Python or Flask backend service.
Key Features
- Standard Filters: upper, lower, trim, length, first, last, join(sep), default(value), and safe.
- Conditionals & Iteration: Supports if/elif/else truthiness branching and for loops over arrays.
- HTML Escaping Toggle: Escaping enabled by default for safe user-facing text, toggleable for raw HTML generation.
- Code & Live Preview Tabs: Inspect raw generated text or view rendered components directly in a sandboxed iframe.
- 100% In-Browser Privacy: No eval and zero server requests: your templates and JSON stay local on your machine.
Frequently Asked Questions
Which filters are supported?
upper, lower, trim, length, first, last, join(sep), default(value), and safe (opts a single value out of escaping).
What is not supported?
Macros, include, extends, arithmetic expressions, and arbitrary Python-style expressions. Unsupported syntax produces a clear error naming what was rejected, rather than silently misbehaving.
Is anything executed on a server?
No. There is no eval or dynamic code execution anywhere in the renderer; it is a small hand-written interpreter running locally in your browser.
Should I turn off HTML escaping?
Only for non-HTML output (plain text, code, config files) or when generating raw styled HTML where tags and CSS should not be escaped. For user-facing HTML templates with untrusted variables, leave escaping on.
