DNS Prism

BIND master file · RFC 1035

Zone file generator

Fill in records and get a clean, aligned BIND zone snippet that you can paste into a zone file or import into a DNS host. Everything is generated on your device.

Names: @ is the zone itself, www is relative, a trailing dot makes a name absolute. TTLs take seconds or units such as 1h.

Records

    Add

    Zone snippet

    
				
    
				
      
			
      
		
      
	
      

	
      
		
      
			
      How to use it
      
			
      Set the zone name and default TTL, then add records with the coloured buttons. The snippet on the right updates as you type, and any record with a problem is held back and explained under its fields. Your draft is kept in this browser only, so it survives a reload.
      
			
      What each part does
      
			
        
				
      • Name: @ for the zone itself, www for www.example.com, * for a wildcard. Typing the full name works too; it is shortened to a relative one.
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      • Targets (CNAME, MX, SRV): names containing a dot, such as mail.example.net, are written as absolute names with a trailing dot, which avoids the classic mistake of BIND appending the zone a second time.
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      • TXT: long values such as DKIM keys are split into 255-byte strings inside parentheses; quotes and backslashes are escaped and non-ASCII bytes are written as \DDD.
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      • CAA: choose issue for the certificate authority allowed to issue, issuewild for wildcards and iodef for violation reports.
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      It also checks for a CNAME at the zone apex, a CNAME sharing its name with other records, and two SPF records at one name.
      
		
      
	
      

	
      
		
      Frequently asked questions
      
		
      
			
      
				What does the trailing dot mean?
				
      A name ending in a dot is absolute. Without it, the zone name is appended, so mail.example.net inside example.com would become mail.example.net.example.com.
      
			
      
			
      
				Can I put a CNAME on the bare domain?
				
      No. A CNAME cannot coexist with other records, and the zone apex always has SOA and NS records. Some DNS hosts offer ALIAS or CNAME flattening instead, which is provider-specific and not part of the zone file standard.
      
			
      
			
      
				Can I import the snippet into my DNS host?
				
      Many DNS hosts accept BIND-format zone files for import, and BIND, Knot and NSD read them directly. A full zone file also needs SOA and NS records, which your DNS host normally creates.