🔍 DNS Record Comparator

What Can the DNS Record Comparator Do?

The DNS Record Comparator is a free online operations tool that compares two sets of DNS records, highlighting added, removed, and changed records. Supports A, AAAA, CNAME, MX, TXT, NS, SOA, SRV, CAA, PTR and other common record types. Ideal for DNS migration verification, DNS change auditing, and configuration comparison. All comparison is done locally in the browser—your data is never uploaded to any server.

Core Features

• Diff Highlighting: Green=added, red=removed, yellow=changed, gray=unchanged
• Multi-record Types: Supports A/AAAA/CNAME/MX/TXT/NS/SOA/SRV/CAA/PTR
• BIND Format Parsing: Supports standard BIND zone file format and simplified format
• Statistics Summary: Shows count of added/removed/changed/unchanged records
• Export Results: Copy and download comparison results in CSV format

Usage Tutorial

1. Paste original DNS records in the left input, new records in the right input.

2. Click "Compare" or use the Ctrl+Enter shortcut.

3. View the diff table: green=added, red=removed, yellow=changed.

4. Click "Copy Result" or "Download CSV" to export comparison results.

Application Scenarios

Scenario 1: DNS Migration Verification

When migrating a domain from one DNS provider to another, compare pre- and post-migration records to ensure nothing is missing.

Scenario 2: DNS Change Auditing

Operations teams compare pre- and post-change DNS records to confirm changes match expectations.

Scenario 3: Multi-environment Configuration Comparison

Compare DNS configuration differences between production and test environments to ensure consistency.

Extended Knowledge

DNS (Domain Name System) is core internet infrastructure that maps domain names to IP addresses. Common record types: A (IPv4 address), AAAA (IPv6 address), CNAME (alias), MX (mail exchange), TXT (text info, often for SPF/DKIM), NS (name server), SOA (start of authority). BIND format is the standard DNS zone file format, one record per line: name TTL class type value. DNS change propagation must account for TTL cache time; it's recommended to lower TTL values before changes to speed up propagation.