All Tools
DNS, email, ports, SSL, WHOIS and 30+ more tools — all in one place. Free web interface and powerful REST API.
6 tools in Utilities
Base64 Encoder/Decoder
Base64 encode and decode online. Convert text to Base64 or decode Base64 strings back to plain text. View size comparison and encoding ratio.
URL Encoder/Decoder
URL encode and decode online using encodeURI and encodeURIComponent. Parse URL structure, extract query parameters, and fix encoding issues.
Hash Generator
Generate MD5, SHA-1, SHA-256, SHA-512 hashes online. Free hash generator for any text with hash comparison and file integrity verification.
JSON Formatter & Validator
Format, validate, and beautify JSON online. Free JSON formatter with minification, structure depth analysis, key counting, and detailed error messages for invalid JSON.
Password Generator
Generate secure passwords online with customizable length, character sets, and strength meter. Free password generator with entropy score and security rating.
UUID / ULID Generator
Generate UUID v1, v4, v7, ULID, and Nano ID. Analyze existing IDs — extract timestamps, detect versions. Custom prefixes, formats, batch generation.
Browse Tools by Category
DNS & Domain Tools (6)
Check DNS records, monitor propagation, perform reverse DNS lookups, query WHOIS data, and verify nameserver configurations for any domain worldwide.
Email & Deliverability Tools (8)
Validate MX records, check SPF/DKIM/DMARC policies, scan IP blacklists, analyze email headers, and run full email health diagnostics to fix deliverability issues.
Network & IP Tools (9)
Scan open ports, run ping and traceroute tests, geolocate IP addresses, look up ASN information, calculate subnets, and check your public IP — all from your browser.
Web & Security Tools (6)
Verify SSL/TLS certificates, inspect HTTP security headers, measure page load speed, detect web technologies, generate security scores, and check robots.txt configurations.
Images & Media Tools (11)
Convert between PNG, JPEG, WebP, and AVIF formats. Resize, crop, optimize, add watermarks, extract EXIF metadata, generate color palettes, and create placeholder images.
Text Tools Tools (7)
Analyze text readability and word count, check content for water words, calculate keyword density, convert letter case, compare text differences, and test regular expressions.
Utilities Tools (6)
Encode and decode Base64 and URLs, generate MD5/SHA hashes, format and validate JSON, create strong passwords, and generate UUIDs — essential developer utilities.
Free Network Diagnostic & Developer Tools Online
NetVizor provides a comprehensive suite of 53+ free online tools for network diagnostics, domain analysis, email troubleshooting, web security auditing, image processing, and developer utilities. Every tool works directly in your browser — no installation, no registration for basic use, and no ads.
DNS & Domain Tools: Our DNS lookup tool lets you query all record types (A, AAAA, MX, CNAME, TXT, NS, SOA) for any domain. Track DNS propagation across global resolvers after making changes. Perform reverse DNS lookups to find hostnames associated with IP addresses. Run WHOIS queries to discover domain ownership, registration dates, and registrar information. Check domain age and verify nameserver configurations — essential for domain research, migration planning, and troubleshooting DNS issues.
Email Diagnostics: Identify why emails bounce or land in spam. Check MX records to verify mail server configurations. Validate SPF records to prevent spoofing. Verify DKIM signatures to ensure email authenticity. Analyze DMARC policies for proper email security. Scan your domain or IP against 50+ DNS-based blacklists (Spamhaus, Barracuda, SORBS). Parse raw email headers to trace delivery paths. Our email health tool combines all checks into a single report card.
Network & Security: Scan open ports on any server to discover running services — check SSH (22), HTTP (80), HTTPS (443), SMTP (25), or custom port ranges. Measure server response time with ping. Trace routing paths with traceroute to identify network bottlenecks. Geolocate any IP address to find its country, city, ISP, and ASN. Verify SSL/TLS certificates and check expiration dates. Inspect HTTP response headers for security misconfigurations. Detect technologies powering any website.
REST API: All tools are available programmatically via our REST API. Get a free API key with 1,000 requests per month. Use it to automate SSL monitoring, DNS validation, port scanning, email health checks, and more in your scripts, CI/CD pipelines, or monitoring dashboards. Paid plans support up to 100,000 requests per month with higher rate limits and bulk endpoints.