I responded to someone in comments on a post that may not get as much visibility, and wanted to share something that might help some others who are newer to this.
I referenced Quad9 DNS as probably one of the best private DNS you can use, Swiss based, no log, no tracking, no data to sell, etc. They also implement DNSSEC, DoH, DoT, QUIC, ECS (which you may or may bot want), malware blocking, content filtering, and maybe something else I’m forgetting.
Many DNS sinkhole apps, OSes, or systems can actually utilize Quad9 for your resolver while those systems also block ads. Below is my functional list of systems that I’m aware of, though I haven’t tested everything. I believe all are considered FOSS, too. If you don’t have a spare Raspberry Pi laying around, try running in HomeAssistant, Yunohost, ZimaOS (previously CasaOS), or others.
DNS sinkhole (Adblocking) apps:
Feel free to comment and add your own I’m maybe not aware of. I’m no software engineer, but I can read through some code, though not an expert, nor have combed through these personally. Usually I’ve tested/run at the recommendation of others over the years before my ban on Reddit (for shitting on AI).
Hope this helps!!


Why would I care about dmarc or dkim when those are used for email hosting services?
You said ad blocking for a dns server that is what you want to use
I’ve never heard of those being used for ad blocking, and not sure how they relate.
DMARC (Domain-based Message Authentication, Reporting, and Conformance) and DKIM (Domain Key Identified Mail) are for authenticating emails and prevents spam or email impersonation. Same with SPF.