# Free Developer Tools for Crawling & Scraping

> Free browser tools for people who fetch the web: robots.txt tester and generator, user agent inspector, cURL to code converter. No sign-up needed.

[Home](https://quanticdata.io/)/Free tools

# Free tools

Small, exact tools for people who fetch the web for a living. Each one runs entirely in your browser: nothing you paste is uploaded, no account is needed, and there is no limit on how often you use them.

[robots.txt tester Test any list of URLs against Googlebot, GPTBot, ClaudeBot or PerplexityBot. Shows the exact rule that decided each verdict, with RFC 9309 precedence.](https://quanticdata.io/tools/robots-txt-tester/) [robots.txt generator Build a valid file from presets, including one that keeps search crawlers while blocking AI training. Every choice explained in plain language.](https://quanticdata.io/tools/robots-txt-generator/) [What is my user agent Your user agent string, what a server reads from it, and the Client Hints that are replacing it.](https://quanticdata.io/tools/user-agent/) [cURL to code converter Paste a curl command, get Python, Node, Go or PHP. Headers, JSON bodies, auth and cookies carried over.](https://quanticdata.io/tools/curl-converter/)

## Why these tools have no sign-up

Every tool here is JavaScript that runs on the page you are reading. There is no upload step, no queue and no account, because there is no server involved in the work. That is a deliberate choice with a practical consequence: you can paste a robots.txt that is not published yet, or a curl command containing a live API key, without it leaving your machine.

It also means the tools keep working if our API is down, and that we cannot rate-limit you.

## What we build the rest of the time

QuanticData runs proxy networks and pay-per-success web data APIs — the infrastructure these tools describe from the outside. If a tool here answers your question, use it and go. If the answer turns out to be “this needs to run across ten thousand pages”, that is the other half of what we do:

- [Web scraping API](https://quanticdata.io/web-scraping-api/) — any page as clean Markdown, HTML or structured JSON.

- [SERP API](https://quanticdata.io/serp-api/) — Google, Bing and DuckDuckGo results as structured data.

- [Crawl & map](https://quanticdata.io/crawl-map/) — discover every URL a site exposes, then fetch them.

- [SEO audit API](https://quanticdata.io/seo-audit/) — crawlability and on-page checks at site scale.

- [MCP server](https://quanticdata.io/mcp-server/) — the same APIs exposed as tools an AI agent can call itself.

## About these tools

### Are these tools really free?

Yes, and there is no account. They run as JavaScript in your browser, so they cost us nothing per use and there is nothing to meter.

### Is anything I paste uploaded?

No. Parsing and generation happen on the page. You can verify it by opening your browser’s Network tab while you use a tool: there are no requests.

### Can I use them at work or in a commercial project?

Yes. Use the output however you like; no attribution is required, though a link is always welcome.

### Do the tools work offline?

Once a page has loaded, yes — the logic is already in your browser.

## Related

[API documentation Every endpoint, one JSON envelope](https://quanticdata.io/docs/) [Blog How we build and measure this](https://quanticdata.io/blog/) [Web data for AI The pillar behind these tools](https://quanticdata.io/ai-web-scraping-service/) [Pricing Pay per successful call](https://quanticdata.io/#pricing)

## Need the same thing across ten thousand pages?

That is what the APIs are for. Free key, $2 of usage credit every month, and you pay only for calls that return a usable result.

[Get my free API key](https://app.quanticdata.io/register)

Free key, $2 of usage credit every month, no credit card.

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Source: https://quanticdata.io/tools/ · Site index for AI: https://quanticdata.io/llms.txt