Skip to content
Toolars
Explore
Report bug

Developer · Local utility

Robots Lab

Test robots.txt agent/path rules, longest-match precedence and before/after crawl-policy changes locally.

Task path / input to outcome

Prepare input

Runs locally · Nothing is uploaded

How Robots Lab works, privacy, and related tools

Task path / input to outcome

How to use

  1. 01

    Prepare input

    Paste content or import a UTF-8 text file. Choose an operation and check the example.

  2. 02

    Review the result

    Run explicitly, compare the output with the original and review every diagnostic before using it.

  3. 03

    Export the result

    Copy or download the current output; export row-level findings separately.

Tool facts

Processing
In your browser
Input leaves this device
Never
Retention
Nothing is stored
Price
Free

Your input stays in the browser.

Robots Lab uses its verified local execution path and does not create a hidden input or output history.

Local execution

Runs inside the current browser tab.

No hidden processing

Active tool data never becomes a Toolars document record.

No account required

Use the core workflow without creating a profile. Favorites sync to your account after you sign in.

Immediate reset

Clear the tab and the active working data is gone.

What Robots Lab actually does

Test robots.txt agent/path rules, longest-match precedence and before/after crawl-policy changes locally.

Common questions

What does Robots Lab support?
RFC 9309 rule matching with specific agent groups, wildcard/end anchors, longest rule and Allow on ties. Empty rules are ignored. Results describe crawling, not indexing. No URL fetches.
Does Robots Lab upload my content?
Your content stays in page memory. Processing runs locally; navigation or reload clears it.
What limits apply to Robots Lab?
256 KiB combined input; 5,000 input rows; depth 40; 10,000 nodes; 2 MiB output. Processing stops after 3 seconds; worker startup allows 15 seconds.

Continue in Developer

Related tasks, not a dead end.

Move into another focused workspace without returning to the full index.

URL Workbench

Clean URL lists with signed-link protection and per-line reasons. Compare components and export sitemaps.

Create

JSON Explorer

Query JSONPath, extract fields and round-trip JSON Pointer records without losing large-number precision.

Create

JSON Schema Validator

Validate Draft 7 or 2020-12 locally with exact error paths; infer schemas from multiple observed samples.

Create

HTML Publishing

Clean pasted HTML for publishing while preserving lists, links and table semantics; preview changes safely.

Create