Warmerly
Checked every six hours per mailbox, with a written fix; domain and IP blocklists.
Warmerly
Folderly
One-to-one · SPF, DKIM, DMARC and blocklist checks
SPF, DKIM, DMARC and blocklist checks
One row, in depth: what each tool does, the verified numbers, and who each suits.
Folderly details read from its pricing page, overview, home page, product sites, terms, privacy policy and help centre on 21 October 2026.
Warmerly
Checked every six hours per mailbox, with a written fix; domain and IP blocklists.
Folderly
Lens checks SPF, DKIM, DMARC, MX, reverse DNS, TLS and blocklists; its free scan covers 10 assets.
The short answer
SPF, DKIM, DMARC and blocklist checks, in one look.
Both check authentication and blocklists. Warmerly re-checks every connected mailbox's records every six hours, probes 51 common DKIM selectors, queries 6 domain and 10 IP blocklist zones, and writes the fix. Folderly's Lens checks a longer list, including reverse DNS, TLS and registration signals, but its free scan covers 10 assets and the frequency of checks in the core product is not stated. Last checked 22 October 2026.
Folderly
Lens checks SPF, DKIM, DMARC, MX, reverse DNS, TLS and blocklists; its free scan covers 10 assets.
The picture
Drawn side by side.
What gets checked
SPF, DKIM, DMARC and blocklists
WarmerlyFolderly
WarmerlyEvery 6 hours, on its own
- SPF10-lookup limit, with a written fix
- DKIMKey length and test mode
- DMARCPolicy and reporting address
- BlocklistsDomain and IP zones
FolderlyRun a scanLens, run as a scan
- SPFWith a recursive lookup count
- DKIMA 16-selector probe
- DMARCEnforcement
- BlocklistsDomains and sending IPs
- rDNS and TLSPTR on sending IPs, TLS
Lens's free scan covers 10 assets. How often the core product re-checks records is not stated.
How often, over a day
Hours from midnight
WarmerlyFolderly
WarmerlyA records sweep every 6 hours
0624 h
FolderlyNot stated for the core product; Lens Monitor says weekly
Folderly does not say how often its core product re-checks records.
On screen
What it looks like.
WarmerlySample data
How Warmerly does it
Warmerly, in detail.
Every six hours, per mailbox, with the zones named, the coverage reported and a written fix. It does not check reverse DNS or TLS.
01
Checked every six hours
The records sweep runs every six hours, so four times in 24 hours, across every mailbox that is not dead or paused. A Re-check now option is on the mailbox Health tab.
Warmerly product, checked 21 October 2026
02
A written fix for each finding
Each finding has a title, an explanation and a fix. SPF is checked for the 10-lookup limit, DKIM for key length and test mode, DMARC for policy and reporting address.
Warmerly product, checked 21 October 2026
03
Domain and IP blocklists
Domains and sending IPs are looked up against published blocklist zones, such as Spamhaus, and a listing raises an alert.
Warmerly product, checked 21 October 2026
04
Unknown is never green
A check that could not run is shown as unknown, not as fine. Unknown also outranks a warning in the overall verdict, because an unknown blocklist status could be hiding a listing.
Warmerly product, checked 21 October 2026
05
SPF is read in depth
Beyond whether a record exists, SPF is checked for its all qualifier, for the RFC 7208 limit of 10 DNS lookups counted through include and redirect, and for ip4 or ip6 terms that hold an address of the wrong family, which voids the record.
Warmerly product, checked 21 October 2026
06
51 common DKIM selectors
A DKIM selector is a name the sending provider chooses, so it cannot be looked up from the domain alone. Warmerly tries the mailbox's saved selector first, then a list of 51 common ones, in small batches with one retry after 5 seconds for any lookup that errored. The code says plainly that the list can never be exhaustive.
Warmerly product, checked 21 October 2026
07
Six domain zones and ten IP zones
Domain lookups use Spamhaus DBL, SURBL, URIBL, NordSpam DBL, Spam Eating Monkey URI and s5h. IP lookups use Spamhaus ZEN, SpamCop, Barracuda, PSBL, Mailspike, NordSpam, Spam Eating Monkey, Lashback UBL, DroneBL and GBUdb Truncate. SORBS (shut down in 2024), UCEPROTECT (pay to delist) and Invaluement (subscription only) are left out on purpose.
Warmerly product, checked 21 October 2026
08
A known limit on the IP check
The sending IP checked is the one behind the mailbox's configured SMTP submission host. For a small or self-hosted server that is the sender's own reputation. For a large provider, mail submitted to its host leaves from a different pool, so the result says less. Reverse DNS and TLS are not in the checks we publish.
Warmerly product, checked 21 October 2026
How Folderly does it
Folderly, in detail.
A longer list of checks in Lens, sold as a separate site and plans, and domain health guides in the main product. The core product's check frequency and blocklists are not stated.
01
Lens checks
Lens lists SPF with a recursive lookup count, a 16-selector DKIM probe, DMARC enforcement, MX, NS and A records, PTR and rDNS on sending IPs, registration-burst signals from RDAP and WHOIS, TLS and DNSBL checks on domains and IPs.
lens.folderly.com · read 22 October 2026
02
A free scan of 10 assets
The free self-serve scan covers 10 assets, and the page says it needs no API keys, no inbox connection and no test sends. The data comes from public DNS, RDAP and WHOIS, HTTP and public DNSBLs.
lens.folderly.com · read 22 October 2026
03
Paid Lens plans
The page lists an Audit at $149 one-time for up to 50 domains, a Monitor at $149 a month, an Agency tier at $499 a month, and an Enterprise route for 100 or more sending domains by contacting sales.
lens.folderly.com · read 22 October 2026
04
What Monitor adds
Monitor lists a weekly re-scan, alerts on new DNSBL hits, SPF and DMARC drift detection, before and after remediation tracking, and a 14-day refund.
lens.folderly.com · read 22 October 2026
05
What the Audit hands over
The Audit includes a full collector run, a per-domain and per-IP CSV register, an HTML report, and the right to keep the output whether or not you fix anything. Each asset gets one of four verdicts, KILL, KILL to REPLACE, REHAB or KEEP, with a driver list and a risk band.
lens.folderly.com · read 22 October 2026
06
Domain health in the main product
The overview page offers in-depth insights on domain technical issues and step-by-step resolution guides, and lists DNS records check and setup support in its comparison table.
folderly.com/overview · read 22 October 2026
07
IP insights and delisting guides
Inbox Insights shows an overview of sending IPs, including their type, sender score and blacklist information. Its comparison table also lists blacklist checks with delisting guides.
folderly.com/email-deliverability-test · read 22 October 2026
What Folderly does not say
We looked, and found no statement on these. That is about its published pages only, not about the product.
- Which blocklists are checked in the core product
- How often the core product re-checks records
- Whether Lens is included in the $96 per mailbox plan, which the pricing page does not say
- Whether the 5 free estate audits a week and the $149 Audit are the same offer
- How the sender score is calculated
Where the sources disagree
We report each version rather than pick one.
- Lens is a separate site with its own plans. Folderly's pricing page does not say whether Lens is part of the $96 per mailbox plan.
The numbers
Only what we could verify.
| Measure | Warmerly | Folderly |
|---|---|---|
| SPF, DKIM, DMARC and blocklist checks | Checked every six hours per mailbox, with a written fix; domain and IP blocklists. | Lens checks SPF, DKIM, DMARC, MX, reverse DNS, TLS and blocklists; its free scan covers 10 assets. |
| Record checks a day | 4, every six hours | Not stated |
| Free scan size | Every connected mailbox | 10 assets |
| Lens Monitor | No separate price | $149 a month |
| DKIM selectors probed | 51 common ones plus the saved one | 16 in Lens |
| Blocklist zones named | 6 domain and 10 IP | Not stated |
| One-off audit | No such product | $149 for up to 50 domains |
| Audit cost per domain at 50 domains | Not applicable | $2.98 |
| Lens Monitor over 12 months | No separate price | $1,788 |
| Reverse DNS and TLS checks | Not in our list | Listed in Lens |
In practice
What it means for you.
Our reading of the facts above. Not a promise, and not the only reasonable reading.
Run its free scan
Lens's free scan is a fair way to see what a wider list of checks finds, with no mailbox connected. It stops at 10 assets, so with 30 domains you would see a third of them.
Check the frequency
Warmerly re-checks four times a day. Lens's Monitor says weekly, and the core product does not say. If a record breaks at 09:00, the longest wait for a Warmerly re-check is six hours. The longest wait on a weekly re-scan is seven days, which is 168 hours.
Pricing a one-off audit against a year of monitoring
An Audit is $149 once for up to 50 domains, which is $2.98 a domain at the full 50. Monitor is $149 a month, so 12 months is $1,788. If you only need a snapshot before launching a batch of domains, the Audit is the smaller bill. If you need ongoing checks on the same mailboxes you warm, Warmerly's are included in the plan.
Running your own mail server
Reverse DNS matters most when you run your own SMTP server, because receivers look at the PTR record of the sending IP. Lens lists PTR and rDNS checks. Warmerly's published checks do not include them, so for a self-hosted server use Lens's free scan alongside Warmerly's records and blocklist checks.
Who it suits
Pick the one that fits.
Warmerly
Warmerly is the better fit if
- You want records checked on a schedule, with no extra price
- You want a written fix for each finding, and the exact SPF or DMARC record to paste
- You want checks and warmup on the same mailboxes
- You want to see which blocklist zones were queried and how many answered
Folderly
Folderly is the better fit if
- You want reverse DNS, TLS and registration checks too
- You want a one-off audit of up to 50 domains with a CSV register
- You want IP type and sender score in one place
- You need a white-label PDF or API access for client reporting
Questions
What does Folderly Lens check?
SPF with a recursive lookup count, a 16-selector DKIM probe, DMARC enforcement, MX, NS and A records, PTR and rDNS, registration-burst signals, TLS and DNSBL listings, per lens.folderly.com (read 22 October 2026). Its free scan covers 10 assets. Warmerly checks SPF, DKIM, DMARC, MX and blocklists every six hours on each connected mailbox.
Does Warmerly check reverse DNS or TLS?
Not in the list we publish. Warmerly checks SPF, DKIM, DMARC, MX, and domain and IP blocklists, and it has a free DMARC and blocklist checker.
How often does Folderly re-check my records?
Lens Monitor lists a weekly re-scan. The core product's frequency is not stated on the pages we read. Warmerly re-checks every six hours.
Which blocklists does Warmerly query?
Six domain zones (Spamhaus DBL, SURBL, URIBL, NordSpam DBL, Spam Eating Monkey URI, s5h) and ten IP zones (Spamhaus ZEN, SpamCop, Barracuda, PSBL, Mailspike, NordSpam, Spam Eating Monkey, Lashback UBL, DroneBL, GBUdb Truncate). Folderly's pages do not list which blocklists they use.
Sources
Folderly pages were read on 21 October 2026. Plans and wording change, so check the vendor's own page before you decide. Warmerly details come from the product as it runs today.
More features
- All features
- Starting price (per month)
- Pricing model
- Cost at 5, 25 and 100 mailboxes
- Free plan or trial
- Warmup and mailbox engagement
- DMARC reports
- Inbox placement tests
- Alerts
- Content and spam-trigger checks
- Campaign sending
- Mailbox providers and sending services
- Agencies, teams and API
- Security and data hosting
See it on your own mailbox.
Connect a mailbox. Warmerly runs alongside whatever you send from now, so you can compare before you move anything.
Free plan, no card. Paid plans: 7-day trial, first charge on day 8.