About DKIMwl.org
A free DNS list for email classification, most useful alongside DKIM-verified mail - how it works, how to query it, and how to read the return codes.
What it is
DKIMwl.org is a domain-reputation service: the unit of reputation is the DKIM signing domain (the d= value), not an IP address. It is the domain-focused sibling of the fmb.la IP DNSBL.
The service observes how often signing domains are queried, lets trusted users vote on each domain's category and a 0-5 trust score, and merges those signals into a reputation used to build a DNS zone. Queries return 127.0.<category>.<0-5>, so a spam filter can welcome-list high-trust senders and score categories as it sees fit.
Scores are derived using the Wilson score interval, so no single user can promote or demote a domain. Get in touch to request an account or report a problem.
Using the list
As long as you abide by the terms of use you are free to filter your mail how you like, but we recommend:
- Check the zone for the signing domain of DKIM-signed emails only where signature verification has passed.
- Skip spam scoring for listed domains whose Trust Level is High.
How to query
Queries go to the zone lookup.dkimwl.org, in the form:
example.com.lookup.dkimwl.org
The zone contains example.com for test lookups. A real lookup:
$ host gmail.com.lookup.dkimwl.org gmail.com.lookup.dkimwl.org has address 127.0.3.3
Return codes
Responses are structured as 127.0.Y.Z - Y is the category and Z is the trust level.
| Y | Category |
|---|---|
| 2 | Bulkmailer |
| 3 | Freemail Provider |
| 4 | Service/Network Providers |
| 5 | Personal/Private Servers |
| 6 | Media & Technology Companies |
| 7 | Organisations |
| 8 | Public Sector & Governments |
| 9 | Travel & Leisure Industry |
| 10 | Financial services |
| 11 | Education & Academic |
| 12 | Manufacturing & Industrial |
| 13 | Retail/Wholesale/Services |
| 14 | Healthcare Services |
| 15 | News Outlet |
| 16 | Mailing Lists |
| 17 | Dating |
| 18 | Money Saving |
| 19 | Jobs & Careers |
| 20 | Social |
| 21 | Real Estate |
| 22 | Marketing |
| 23 | Tickets |
| 24 | Gambling |
| 25 | Food & Restaurants |
| 26 | Business |
| 27 | Faith & Religion |
| 28 | Stocks & Shares |
| 29 | Arts |
| 30 | Sports & Recreation |
| 128 | Special / Other Service |
| Z | Trust level |
|---|---|
| 0 | Blacklisted |
| 1 | Low |
| 2 | Low-Med |
| 3 | Med |
| 4 | Med-High |
| 5 | High |
Trust levels explained
Low - occasional spam issue; problems dealt with less promptly.
Med - occasional spam issue, dealt with promptly; user opt-in and opt-out mail.
High - rare spam issue, dealt with promptly/proactively; 100% opt-in and opt-out; mail that should reach the inbox.
SpamAssassin examples
Examples only - build full rules to taste by adjusting the regexes.
Simple welcome-listing
# Welcome-list all high-trust domains askdns DKIMWL_WL _DKIMDOMAIN_.lookup.dkimwl.org A /^127\.\d+\.\d+\.5$/ tflags DKIMWL_WL nice net describe DKIMWL_WL DKIMwl.org - Welcome-listed sender score DKIMWL_WL -7.5
Category scoring
# Welcome-list high-trust financial domains askdns DKIMWL_FINANCIAL_WL _DKIMDOMAIN_.lookup.dkimwl.org A /^127\.\d+\.10\.5$/ tflags DKIMWL_FINANCIAL_WL nice net score DKIMWL_FINANCIAL_WL -1.0 # Add scoring to any low-scoring bulkmailer askdns DKIMWL_BULKMAILER_LOW _DKIMDOMAIN_.lookup.dkimwl.org A /^127\.\d+\.2\.[0-2]$/ tflags DKIMWL_BULKMAILER_LOW net score DKIMWL_BULKMAILER_LOW 1.0
Magnitude scores
Like the Richter scale, magnitude is a base-10 log measure of message volume: a one-point drop means roughly 10x less volume. The table shows the share of DKIM-signed email at each magnitude.
| Magnitude | Share |
|---|---|
| 10.0 | 100% |
| 9.0 | 10% |
| 8.0 | 1% |
| 7.0 | 0.1% |
| 6.0 | 0.01% |
| 5.0 | 0.001% |
| 4.0 | 0.0001% |
| 3.0 | 0.00001% |
| 2.0 | 0.000001% |
| 1.0 | 0.0000001% |