Free Developer Tools

Request one URL from a datacenter IP and residential IPs at once, and see which of them gets blocked.

What your HTTP client gives away: header order, missing client hints, and contradictions with your user-agent.

Five questions and a straight answer, including when the answer is that you do not need proxies at all.

Your public IP address, the country it resolves to, reverse DNS and the headers your browser sends.

• Public IPv4 or IPv6 address
• Country and reverse DNS when they resolve
• The request headers your browser sends

Derive how many proxies a job needs from volume, deadline, per-IP rate limit, concurrency and retries.

• Rate floor and concurrency floor, side by side
• Retry multiplier and bandwidth for the run
• Says whether per-IP or per-GB fits

Check a path against a pasted robots.txt and see the exact rule that allowed or disallowed it.

• Allowed or disallowed, and the line that decided
• Longest-match precedence, wildcards and anchors
• Your pasted file: nothing is fetched

Paste a curl command and read it back as Python, Node.js, Go or PHP, with the flags translated properly.

• Python requests, Node fetch, Go and PHP
• Reads headers, bodies, auth, proxies and forms
• Names every flag it could not translate

Turn a proxy host, port and credentials into working curl, Python, Node.js and Scrapy snippets.

• curl, Python, Node.js, Scrapy and env vars
• HTTP, HTTPS, SOCKS5 and SOCKS5h schemes
• Credentials URL-encoded correctly

Network address, broadcast, usable range and host counts for any CIDR prefix length.

• Network, broadcast and usable host range
• Netmask, wildcard mask and binary form
• IPv4 and IPv6, /0 through /128

Decode any user-agent string into browser, engine, OS and device, including bots and HTTP libraries.

• Browser, engine, OS and device type
• Detects crawlers, CLIs and HTTP libraries
• Runs entirely in your browser