WarmerlyWarmerly ahead on this row
Records checked every six hours with a written fix; 16 named blocklists, 6 for domains and 10 for IPs.
Warmerly
Warmup Inbox
One-to-one · SPF, DKIM, DMARC and blocklists
SPF, DKIM, DMARC and blocklists
One row, in depth: what each tool does, the verified numbers, and who each suits.
Warmup Inbox details read from its pricing page, home page, product pages, API page, integrations pages, help centre, legal pages and status page on 21 October 2026.
Warmerly
Records checked every six hours with a written fix; 16 named blocklists, 6 for domains and 10 for IPs.
Warmup Inbox
Checks are built in; its pages give 100+ blacklists daily, 50+ hourly and 4 IPv4 lists, with no named list or interval.
The short answer
Authentication and blocklist checks, in one look.
Both check SPF, DKIM, DMARC and blocklists. Warmerly says exactly how often (every six hours), names the 16 blocklist registries it queries, six for domains and ten for IPs, and writes a fix for each finding. Warmup Inbox says its checks are built in but gives three different blacklist counts on its own pages: 100+ checked daily, 50+ rechecked hourly, and the four most common IPv4 lists in a help article. On what is published, Warmerly is clearer. Warmup Inbox says more about automatic rescue and alerts. Last checked 21 October 2026.
Warmup Inbox
Checks are built in; its pages give 100+ blacklists daily, 50+ hourly and 4 IPv4 lists, with no named list or interval.
The picture
Drawn side by side.
How the records get checked
SPF, DKIM and DMARC
WarmerlyWarmup Inbox
WarmerlyEvery 6 hours, on its own
- SPFchecked
- DKIMchecked
- DMARCchecked
Warmup InboxInterval not stated
- SPFbuilt in
- DKIMbuilt in
- DMARCbuilt in
Warmerly writes the fix for each finding. Warmup Inbox says it does not change your records.
On screen
What it looks like.
WarmerlySample data
How Warmerly does it
Warmerly, in detail.
A six-hourly records check per mailbox with a written fix, sixteen named blocklist registries, alerts that fire only for real failures, and free DMARC report collection.
01
Records checked every six hours
The records sweep runs every six hours by default across every mailbox that is not dead or paused. The mailbox Health tab has a Re-check now option. Blocklist checks run on their own six-hourly sweep, and a manual re-check is limited to once every six hours.
Warmerly product, checked 21 October 2026
02
More than whether a record exists
SPF is checked for its ending, the 10-lookup limit and broken terms. DKIM is checked for key length and the t=y test flag. DMARC is checked for p=, sp=, pct= and whether rua= is set. MX is checked for presence, since warmup needs replies.
Warmerly product, checked 21 October 2026
03
Sixteen named registries
Six for domains: Spamhaus DBL, SURBL, URIBL, NordSpam DBL, Spam Eating Monkey URI and s5h. Ten for IPs: Spamhaus ZEN, SpamCop, Barracuda, PSBL, Mailspike, NordSpam, Spam Eating Monkey, Lashback UBL, DroneBL and GBUdb Truncate.
Warmerly product, checked 21 October 2026
04
A written fix, sometimes the exact record
Each finding has a title, an explanation and a fix. For a failing SPF or DMARC chip the card can show the record itself, with a copy button. DKIM values for third-party mailboxes are not generated; the fix text points to your provider.
Warmerly product, checked 21 October 2026
05
Unknown is never green
A check that could not run is shown as unknown, never green, and unknown outranks a warning in the overall verdict. A known limit: DKIM is found by trying common selector names plus any you set, so an unusual selector can read as no signature until you enter it.
Warmerly product, checked 21 October 2026
06
Alerts for real failures only
A hard failure raises a DNS changed alert with a 24-hour cooldown. Quality advisories such as DMARC p=none are shown but never red and never alert. A domain or IP listing raises an alert. Alerts are grouped into at most one email per user per 24 hours.
Warmerly product, checked 21 October 2026
07
Free DMARC reports
Point your DMARC rua address at a Warmerly address to see who sends as your domain and whether they pass, for up to 10 domains per workspace. Email digests and alerts for these reports are not built.
Warmerly product, checked 21 October 2026
How Warmup Inbox does it
Warmup Inbox, in detail.
Authentication and blacklist checks described as built in and real-time, with blacklist counts that vary between pages and a help article listing four IPv4 lists.
01
Built-in checks
The home page says DNS, SPF, DKIM and blacklist checks are built in, and that inbox, spam and bounce rates are tracked in real time. The how-it-works page says it checks DNS settings, DMARC, DKIM, SPF, domain age and security protocols.
warmupinbox.com/how-it-works · read 21 October 2026
02
100+ blacklists, checked daily
The home page says it watches 100+ blacklists daily and that when an inbox gets listed, rescue runs automatically. Its example lists Spamhaus ZEN and Barracuda as Clear, SpamCop as Rescued in 36h and SORBS as Clear.
warmupinbox.com · read 21 October 2026
03
50+ blacklists, rechecked hourly
A dashboard mock on the same home page reads Re-checked hourly across 50+ blacklists with Sender IP Clean, Sending domain Clean and Active listings 0. Its Mailwarm comparison also says blacklist monitoring across 50+ blacklists with hourly rechecks.
warmupinbox.com/mailwarm-alternative · read 21 October 2026
04
The help article says four
A help article dated 1 May 2024 says that once you sync an inbox it checks the IP address of your domain against the 4 most common IPv4 blacklists, and shows a confirmed match on the primary dashboard. It does not name the four or say how often it repeats.
help.warmupinbox.com/en/articles/4741859-blacklists-explained · read 21 October 2026
05
Health score bands
The health score article gives bands: 0% to 65% low, 65% to 80% ok, 80% to 100% good. It says under 80% can mean the inbox is not fully configured with the proper DNS settings or is listed on a blacklist. It does not explain how the score is calculated.
help.warmupinbox.com/en/articles/4741858-health-score-explained · read 21 October 2026
06
A blacklist checker and generators
The free blacklist checker on its site says it checks a domain or IP with no signup, and its page data lists 100+ blacklist servers. It also has free SPF and DMARC generators, a spam checker, and an email health checker.
warmupinbox.com/tools/blacklist-checker · read 21 October 2026
07
It leaves DNS to you
The Zoho page says your domain should already have proper SPF, DKIM and DMARC, that Warmup Inbox does not change them, and that if records are missing you should run a placement test first. Max includes a technical setup check.
warmupinbox.com/integrations/zoho-warmup · read 21 October 2026
What Warmup Inbox does not say
We looked, and found no statement on these. That is about its published pages only, not about the product.
- A list of the blacklists it checks, beyond four named in the home page example
- How often DNS records are checked, as opposed to blacklists
- A written fix or an example record for a failed SPF, DKIM or DMARC check
- How the health score is calculated, or which scale it uses
- What an alert looks like, how it is delivered, or whether you can set thresholds
- How the 100+ and 50+ blacklist figures relate, or how delisting is carried out
Where the sources disagree
We report each version rather than pick one.
- The home page says 100+ blacklists daily and 50+ hourly; the blacklist checker's page data says 100+ servers; a help article says 4 IPv4 lists.
- The health score article says a score of 1-10 in its header and a reputation score between 1-100 in its body, with bands shown as percentages.
- The Zoho page says no DNS work is required, while its FAQ says your domain should already have SPF, DKIM and DMARC and to run a placement test if records are missing.
The numbers
Only what we could verify.
| Measure | Warmerly | Warmup Inbox |
|---|---|---|
| SPF, DKIM, DMARC and blocklists | Records checked every six hours with a written fix; 16 named blocklists, 6 for domains and 10 for IPs. | Checks are built in; its pages give 100+ blacklists daily, 50+ hourly and 4 IPv4 lists, with no named list or interval. |
| Authentication check interval | Every 6 hours | Not stated |
| Blocklist checks | 16 named registries: 6 domain, 10 IP | 100+ daily, 50+ hourly, or 4 IPv4 lists |
| Blocklists named | All 16 | 4 in an example, none in the article |
| Written fix per finding | Yes, sometimes the exact record | Not stated |
| Health score scale | 0 to 100, weighted 50, 20, 15, 15 | Bands 0 to 65, 65 to 80, 80 to 100, method not stated |
| Alert email cadence | At most one a day per user | Not stated |
| Free DMARC reports | Up to 10 domains | A free DMARC generator, no reports stated |
| Blocklist rescue | Alert only, no delisting | Stated: automatic, 36 hours in its example |
In practice
What it means for you.
Our reading of the facts above. Not a promise, and not the only reasonable reading.
Count the claims, not the number
Warmup Inbox gives 100+, 50+ and four for what looks like the same feature. They may all be true, for example four IPv4 lists for IP checks and more for domains, but the pages do not say so. When a number varies by page, ask for the list.
A named list is checkable
Because Warmerly names its 16 registries, you can look up a domain on any of them yourself, or check the free blacklist checker on both sides. A count with no names asks you to trust it, which is fine until it is the thing you need to prove.
Fix instructions save time
A check that says SPF is broken is useful, and one that says add a TXT record starting v=spf1 is faster. Warmerly writes the second kind. If Warmup Inbox does, we did not find it on its pages, and the setup check on Max may cover it.
Neither tool fixes your DNS for you
Both tell you what to change and leave the change to you. Warmup Inbox says outright that it does not change your records. Warmerly shows the record to paste and says it does not generate DKIM values for third-party mailboxes.
Delisting is a promise to test
If a blacklist listing is a recurring problem for you, ask Warmup Inbox what happens after it says rescue runs automatically, and how the 36 hours in its example is measured. We check and alert and do not delist.
Who it suits
Pick the one that fits.
Warmerly
Warmerly is the better fit if
- You want to read exactly which blocklists are queried and how often
- You want a written fix and sometimes the exact record to add
- You want unknown results shown as unknown rather than fine
- You want free DMARC report collection for up to 10 domains
- You want alerts limited to real failures and one email a day
Warmup Inbox
Warmup Inbox is the better fit if
- You want a tool that also claims to act on a blacklist listing
- You want a technical setup check on Max
- You like a banded health score with a clear meaning for each band
- You want free generators and a free blacklist checker beside the product
- You want alerts described alongside a ramp pause, as its home page shows
Questions
How often does Warmerly check DNS?
Every 6 hours. It queries 16 named blocklist registries, 6 for domains and 10 for IPs, and writes a fix for each finding.
How many blocklists does Warmup Inbox check?
Its own pages say 100+ daily, 50+ hourly, or 4 IPv4 lists in a help article.
Does either delist me automatically?
Warmerly alerts only and does not delist. Warmup Inbox says rescue is automatic, with 36 hours in its example.
Does Warmerly include DMARC reports?
Yes, free for up to 10 domains. Warmup Inbox has a free DMARC generator but states no reports.
Sources
- Warmup Inbox home page
- Warmup Inbox how it works
- Warmup Inbox help centre, blacklists explained
- Warmup Inbox help centre, health score
- Warmup Inbox blacklist checker
- Warmup Inbox Zoho page
- Warmup Inbox compared with Mailwarm (its own page)
Warmup Inbox 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)
- Cost at 5 and 25 mailboxes
- Free plan or trial
- What each tier adds
- Warm-up volume per mailbox
- Warmup network size
- Spam rescue
- Languages, templates and ESP targeting
- Placement test
- Supported mailboxes and sign-in
- Campaign sending
- API access
- Agency and client workspaces
- Data, support and terms
See it on your own mailbox.
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