DNS & domain lookup

DNS Diff Tool

Compare two DNS zones or record sets and see exactly what was added, removed and changed. Free DNS diff, runs entirely in your browser.

Compare two DNS record sets

Paste the old records on the left and the new records on the right (zone-file lines).

Before
After

What this DNS diff tool does

Compares two zone files or record sets
Highlights added, removed and changed records
Detects value changes for the same name and type
Ignores comments, order and whitespace
Shows a clear before/after for each change
Runs entirely in your browser

Common use cases

  1. 1Reviewing DNS changes before applying them
  2. 2Comparing a zone before and after a migration
  3. 3Auditing what a provider actually changed
  4. 4Confirming a bulk edit did only what you intended
  5. 5Documenting DNS changes for a change log
  6. 6Catching accidental record deletions

Related tools

DNS zone file validatorDNS Record LookupDNS Health CheckerDNS Propagation CheckerTXT record splitterNameserver migration checker

About comparing DNS records

When you migrate DNS providers or edit records in bulk, it is easy to drop or mistype a record. Comparing the before and after record sets shows exactly what changed — additions, removals and value changes — so nothing slips through.

This tool parses both sides as zone-file records, normalises order and whitespace, and reports the differences. It runs locally in your browser, so you can safely paste production records.

More Free Tools Where This Came From

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HostCloud.in  ·  Pune, India  ·  Serving 34,987+ Websites Since 2020

FREQUENTLY ASKED QUESTIONS

Got Questions? We Have Answers.

What does the DNS diff tool do?

It compares a "before" and "after" set of DNS records (zone-file lines) and shows the additions, removals and value changes, ignoring order and whitespace.

When should I use it?

Before applying DNS changes, after a bulk edit, or when migrating providers — to confirm exactly what changed and catch accidental deletions.

What format should I paste?

Zone-file style lines such as "@ IN A 203.0.113.10". The tool parses both sides the same way, so exports from most providers work.

How does it detect a changed record?

When the same name and type appear on both sides but with different data, it is reported as a change with a clear before and after.

Is my data uploaded?

No. The comparison runs entirely in your browser, so you can safely paste production records.

Does record order matter?

No. The tool normalises order and whitespace, so only real differences in records are reported.