Free DNS, Email & Developer Tools

Free DNS, Email & Network Tools
Built for IT Professionals

DNS Tools

Query A, AAAA, MX, TXT, SPF, DKIM, DMARC and more across multiple resolvers

DNS Propagation

Check propagation across 20 global public resolvers simultaneously

Domain and IP WHOIS with full RDAP data, ASN and network info

Inspect certificate expiry, SANs, chain validity and TLS version

Your public IP address with location, ISP, ASN, hostname and timezone

Domain Age Checker

Find when a domain was registered, when it expires and who the registrar is

Technology Partner Lookup

Identify which vendors a domain has authorised from its DNS TXT records

HTTP Header Checker

Inspect response headers, security grade and redirect chain for any URL

Email Tools

Blacklist Checker

Check IP and domain against 20 DNSBL and URIBL lists in parallel

Deliverability Tester

Full email health check — SPF, DKIM, DMARC, PTR, blacklists, score out of 100

Header Analyzer

Parse raw email headers — auth results, relay hops and timing

SPF Macro Tester

Expand and debug SPF macros for any sender IP and envelope domain

SPF Record Expander

Recursively expand SPF includes to show every permitted IP subnet

Test SMTP servers and check for open relay configuration

DMARC Report Analyzer

Paste or upload a DMARC aggregate XML report to analyze SPF, DKIM and disposition results

Developer Tools

Encode, decode, URL encode, file to Base64 and JWT decoder

Hash Calculator

Hash files, text or URLs using MD5, SHA-1, SHA-256, SHA-384 and SHA-512

Content Analyser

Extract metadata, MIME type and text from any file — PDF, Office, images, audio and more

Subnet Calculator

CIDR notation, host ranges, binary visualiser and subnet breakdown

Test regular expressions with Python, PCRE and ECMAScript engines

HAR & JSON Viewer

Waterfall chart, request details and interactive JSON tree explorer

Timestamp Converter

Convert Unix, ISO 8601, UTC and local timestamps in both directions

Live preview editor with syntax highlighting and 13 built-in snippets

Add cities and compare time zones side by side with hour tiles

Password Generator

Cryptographically secure passwords — custom length, charset and complexity

Resources

API Integration

Programmatic access to all tools via REST API — create an account and generate API keys

Step-by-step guides for all tools — tips, use cases and practical examples

Answers to common questions about every tool on the site

About DigInterface — why it was built and what it is