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View All Online ConvertersQuery String Validator
Validate a raw query string or full URL instantly and review encoding problems, repeated keys, empty values, warnings, and errors.
Validate a query string before you ship or debug it
Paste a raw query string or full URL to check validity, spot encoding problems, and review repeated keys, empty values, and common warnings.
Check whether a query string is valid and what needs attention
Use Query String Validator when you need to check tracking links, callback payloads, copied URLs, or raw query strings for malformed encoding, repeated keys, empty values, and other common issues before shipping or debugging. It also works well when you want to validate query params or validate URL parameters without checking each pair manually.
Paste a raw query string or a full URL to validate it.
Query string validation result
Review the valid or invalid state first, then compare parameter metrics and issue details.
Ready Query string required
Paste a raw query string or full URL above and click "Validate query string" to check it.
Validation issues No issues checked yet
No validation result yet
Paste a query string above and click "Validate query string"
How to use the query string validator
- Paste a raw query string or a full absolute URL into the input box.
- Click Validate query string to run the checks.
- Review the valid or invalid state first.
- Use the metrics to compare parameter count, repeated keys, empty values, warnings, and errors.
- Read the issue list to see what should be fixed or reviewed before shipping the URL.
Query string validator examples
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validate utm_source=newsletter&utm_medium=email
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is q=100% a valid query string
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check https://example.com?ref=docs&ref=search&empty=
What this query string validator checks
This tool validates the query string layer of a URL. It checks common issues such as malformed percent encoding, repeated keys, empty values, raw spaces, and parameter segments that do not include an equals sign. It is meant to help with practical debugging, not replace a full RFC reference.
When query string validation is useful
A query string validator is useful when you need to check campaign links, callback URLs, app redirects, or copied query parameter payloads before sending them to users, APIs, or analytics systems. It is especially helpful when a link looks almost right but still fails because of encoding or parameter mistakes.
Warnings vs errors
This page separates warnings from errors. Invalid percent encoding is treated as a blocking error because it can break the query string. Repeated keys and empty values are shown as warnings because they can still be intentional in some workflows.
Query string validator FAQs
Can I paste a full URL instead of only the query string?
Yes. If you paste a full absolute URL, the validator extracts the query string first and validates the extracted part.
Are repeated query parameters invalid?
Not always. Repeated keys are shown as warnings because they can be intentional, but they are worth reviewing.
What counts as an invalid query string here?
Malformed percent encoding counts as invalid in this version. Other issues such as empty values or repeated keys are surfaced as warnings instead of fatal errors.