Portable Fast URL Checker: High-Speed, Low-Latency Link Scanner

Portable Fast URL Checker — Instant URL Health & Response Times

What it is

• A lightweight, portable tool (no installation required) that validates URLs quickly and reports status codes, response times, redirects, and basic content checks.

Key features

• Fast bulk checking: Concurrent requests with configurable concurrency to test thousands of URLs quickly.
• Instant health indicators: HTTP status, response time, DNS resolution time, TLS handshake time.
• Redirect tracing: Full redirect chain with final URL and cumulative response time.
• Portable distribution: Single binary or standalone script runnable from USB or temporary environments.
• Output formats: CSV, JSON, and human-readable console output for easy integration.
• Retry & timeout controls: Configurable timeouts and retry policies for flaky endpoints.
• Filtering & categorization: Group by status (OK, Redirect, Client Error, Server Error, Timeout).
• Basic content checks: Optional keyword presence, content-length validation, or regex match.
• Rate limiting & politeness: Request rate controls and concurrency limits to avoid overloading targets.
• Summary stats: Totals, success rate, average/median response times, slowest/fastest endpoints.

Typical use cases

• Link validation for websites, documentation, and newsletters.
• Monitoring landing pages and campaign URLs.
• Pre-deployment checks for large URL lists.
• Quick audit from a laptop or USB drive without installing dependencies.

Example output (CSV) id,url,status,response_ms,final_url,redirects,notes 1,https://example.com,200,123,https://example.com,0,OK
2,http://old.example.com,301,45,https://example.com,1,Redirect
3,https://missing.example/404,404,20,https://missing.example/404,0,Client Error

How to run (typical CLI)

• Command pattern: checkurls –input urls.txt –concurrency 50 –timeout 5s –output results.csv
• Common flags: –retry N, –follow-redirects, –user-agent, –rate 100/s, –match “keyword”

Performance tips

• Increase concurrency for high-bandwidth environments; balance with target server capacity.
• Use DNS caching and HTTP connection pooling to reduce per-request overhead.
• Run from a server close to your targets to reduce latency, or distribute checks geographically.

Security & etiquette

• Respect robots.txt and terms of service.
• Avoid aggressive scanning on third-party domains without permission.
• Use identifiable User-Agent and contact info when performing large scans.

Integration ideas

• Schedule with cron and push CSV/JSON to monitoring pipeline.
• Integrate with CI to validate links before deploys.
• Combine with alerting to notify on increased 4xx/5xx or slow responses.