Is my input uploaded?

No. The website version runs locally. Input is sent only when you intentionally use the authenticated API.

Does this use a paid third-party API?

No. The result is calculated from local logic or a bundled reference dataset.

Should I independently verify the output?

Yes. Heuristic, security, legal and reference results should be checked against the authoritative source before important use.

Browser Games

Chess Move Validator

Validate SAN or coordinate chess moves from the starting position or a supplied FEN and return the resulting position.

Free foreverRuns in your browserNo sign-up

SAN or coordinate moveFEN position (optional)

Result

Enter your values and select validate move.

About the Chess Move Validator

Chess Move Validator is a deterministic browser utility. Validate SAN or coordinate chess moves from the starting position or a supplied FEN and return the resulting position.

Processing happens locally in the website tool. The matching authenticated API endpoint uses the same shared implementation for consistent results.

Key features

Private browser-side processing
Structured copy-ready output
Shared website and API behavior
No paid external service

How to use

1Enter the requested value or document.
2Select any available options.
3Run the tool and review the structured result and stated limitations.

Examples

Chess Move Validator example

The interactive tool includes an editable representative input.

Frequently asked questions

Is my input uploaded?: No. The website version runs locally. Input is sent only when you intentionally use the authenticated API.
Does this use a paid third-party API?: No. The result is calculated from local logic or a bundled reference dataset.
Should I independently verify the output?: Yes. Heuristic, security, legal and reference results should be checked against the authoritative source before important use.

Chess