How to Test (specific) DNS Abilities/Hinderances

[Ceyarrecks]

Excuse me Please:

I am well aware of Mr. Gibson's DNS Benchmark tool which I use quite frequently of late.
Speed of resolution is great; However, now that security is of greater import, and singular DNS providers that have more security being preferential, while most carriers view their clients as Vultures whom view their kill just prior to swooping down, I am seeking something more specific in terms of testing DNS.
Background:
*I am on a WISP connection (formerly Sprint, presently on tmobile that bought Sprint some months back)
*i noted in times past ShieldsUP! would identify me as ...sprintsoandso...
*currently ShieldsUP! identifies me as ue.tmodns.net
*note also, that Arstechnica posted a reminder about "tmobile gives arbitrary date to optout before they start selling your data"
{which noting, i was unable to find on any of my Sprint account pages a means to optout}

Further, I note some people using NextDNS are experiencing DNS Resolution/browsing problems with specific errors as quoted below.

This network is blocking encrypted DNS traffic.
The names of websites and other servers your devices accesses on this network may be monitored and recorded by other devices on this network.

Which they stated once they switched off NextDNS/encryption, their browsing was uninterrupted.
(showing OBVIOUSLY their carrier is purposefully collecting data, and actively preventing security.)

Also, over the last, oh, maybe month of so, I have been noting a weird inability to browse the Internet.
Now it need be stressed that NOTHING has changed on my system over last 6mo. or so (probably longer)

So.
Be there a tool that can Test & IDENTIFY one's connection for abilities/hindrances/annoyances/et al using DoH or other secure means of resolving/browsing?

 

[MichaelRSorg]

First, knowing which DNS servers your operating system and web browser are using can be hard. To that end, I have a list of tester web pages here

Test Your DNS Servers - RouterSecurity.org

Test your DNS Servers - kick the tires

www.routersecurity.org

There is also a cheat sheet for nslookup for Windows users to see which DNS servers their OS is using outside of the browsers.

Now that we have encrypted DNS support in most every desktop browser, I suggest you try it out. You can have each browser configured with a different encrypted DNS provider. And, don't forget to try a VPN, as that changes everything about DNS too.