JavaScript Validator
Check JavaScript for syntax errors and get the exact line and column of the first problem. Choose module or script parsing. Runs entirely in your browser.
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End the manual growth tax.
Running checks by hand eats valuable agency time. Uptimeify monitors your entire client portfolio from one place: on a fair, organization-wide quota model, on secure EU infrastructure. No per-client fees, no surprises.
Frequently asked questions about JavaScript Validator
Module mode parses your code as an ES module, so import and export statements and top-level await are allowed and strict mode is implied. Script mode parses a classic script, where a top-level return is allowed (as in a CommonJS wrapper) but import and export are not. Pick the mode that matches how the code will run.
No. It only parses your code to check that the syntax is valid; it never executes it, and it is not a style linter. Parsing runs entirely in your browser with Acorn, nothing is uploaded. As an EU-built, EU-hosted provider, Uptimeify keeps your workflow off US infrastructure and clear of US Cloud Act exposure.
A single syntax error can take a whole page down. Validate scripts before you ship, then let Uptimeify watch the live site from multiple EU locations, if a broken deploy slips through, you get an alert within seconds instead of hearing it from a client.
Ready to Test the Journeys, Not Just the Syntax?
Syntactically clean is not the same as working. Uptimeify walks real flows like login or checkout with Playwright and reports the break before it costs revenue.