Warmerly
An email digest, at most one a day; health webhooks on the Agency plan; no Slack alert found.
Warmerly
Folderly
One-to-one · Alerts
Alerts
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
An email digest, at most one a day; health webhooks on the Agency plan; no Slack alert found.
Folderly
Pulse, listed as free, sends spam alerts by email, Slack and SMS or other tools.
The short answer
Alerts, in one look.
Warmerly raises an email digest, at most one a day, and sends health webhooks on the Agency plan. We found no Slack alert in Warmerly. Folderly's Pulse is listed as free and sends spam alerts by email, Slack (direct and channel messages), SMS and other tools. Folderly is ahead on channels. Last checked 22 October 2026.
FolderlyFolderly ahead on this row
Pulse, listed as free, sends spam alerts by email, Slack and SMS or other tools.
The picture
Drawn side by side.
From a change to your eyes
As each describes it
WarmerlyFolderly
Warmerly
Check runs every 15 minutesAlert raisedOne email digest a day
Folderly
Placement checked regularlySpam alert raisedEmail, Slack or SMS
Warmerly's webhooks, for score drops and DNS changes, need the Agency plan. We found no Slack alert in Warmerly.
Where alerts arrive
As each company states it
WarmerlyFolderly
- At most one email per user a day
- Health webhooks on Agency
- No Slack alert found
Email, Slack and SMS
- Slack direct and channel messages
- Pulse is listed as free
- Check frequency is not stated
Read on folderly.com on 21 October 2026.
How Warmerly does it
Warmerly, in detail.
An email digest, and webhooks on Agency.
01
An email digest
Alerts are grouped and sent as at most one email per user per 24 hours. A repeat of an unchanged problem does not send another.
Warmerly product, checked 21 October 2026
02
What raises one
A health score that falls 15 points or more or sits below 50, a mailbox that disconnects, DNS changes, and a domain or IP blocklisting.
Warmerly product, checked 21 October 2026
03
The engine runs every 15 minutes
The alerts job evaluates mailboxes every 15 minutes, then the digest goes out at most once a day.
Warmerly product, checked 21 October 2026
04
Health webhooks on Agency
Signed webhooks send mailbox health events such as score drops, authentication failures and DNS changes. They need the Agency plan.
Warmerly product, checked 21 October 2026
05
No Slack alert found
We found no Slack alert in the alerts code.
Warmerly product, checked 21 October 2026
06
Seven kinds of alert
The engine raises score drop, score floor, disconnected or failed sign-in, DNS changed, domain blocklisted, IP blocklisted and delivery unobservable. None of the seven is a placement alert.
Warmerly product, checked 21 October 2026
07
An unchanged problem is not repeated daily
Each alert records what it was about. A different or worse fault can alert again after 24 hours. The same fault, still unfixed, waits 14 days, and the title then says still so a reminder does not read as a duplicate.
Warmerly product, checked 21 October 2026
08
Fixed before the digest means never mailed
An alert is withdrawn only when a new measurement clears the condition, never because time has passed. A fault fixed before the daily digest goes out is dropped from it.
Warmerly product, checked 21 October 2026
09
New mailboxes are given 14 days
Score drop and score floor alerts are held back for 14 days after warmup starts, or while there are fewer than 3 health snapshots, because a few early messages in spam move the score by tens of points. Alerts a customer can act on, such as a failing sign-in, a missing SPF record or a blocklisting, still fire on day one.
Warmerly product, checked 21 October 2026
10
Auto-pause has no notification of its own
A mailbox whose health sits below 60 for 2 days is paused automatically. The score floor alert is the only way the owner hears about it, so paused mailboxes still raise score alerts.
Warmerly product, checked 21 October 2026
11
Webhook limits and the event list
The documented list has 16 event types, including DNS changed, auth fail, auto paused and aged in. Each user can hold 10 subscriptions, and the target must be a public https URL. The list has no blocklist event, so a blocklisting reaches you by email digest only.
Warmerly product, checked 21 October 2026
12
Deliveries stop with the plan
Webhook deliveries pause, without counting as failures, while the owner is not on the Agency plan.
Warmerly product, checked 21 October 2026
How Folderly does it
Folderly, in detail.
Real-time placement alerts, listed as free.
01
Pulse is real-time
Pulse is described as monitoring email deliverability with real-time alerts, to detect and address issues as they happen.
folderly.com/email-deliverability-monitoring · read 22 October 2026
02
Email, Slack and more
Its page says you receive spam alerts through email, Slack (direct and channel messages) and other tools, and mentions syncing to email, SMS and Slack.
folderly.com/email-deliverability-monitoring · read 22 October 2026
03
Listed as free
The pricing page says Pulse is free, with real-time alerts at $0 a month, and shows no limits. The pricing page lists the channels as Email, Slack, SMS and other channels.
folderly.com/pricing · read 22 October 2026
04
Placement-based
You specify an inbox rate, a mailbox, a template and the providers to monitor. The page says checks run regularly and gives no frequency.
folderly.com/email-deliverability-monitoring · read 22 October 2026
05
An alert every time mail hits spam
The page says you get alerted every time you hit the Spam folder, and that problems are addressed the moment a deliverability issue is detected through notifications.
folderly.com/email-deliverability-monitoring · read 22 October 2026
06
What you set up
You specify an inbox rate, a mailbox, an email template and the providers to monitor. Gmail and Outlook are named as supported providers, and Folderly connects by API and SMTP.
folderly.com/email-deliverability-monitoring · read 22 October 2026
07
A dashboard of what works
Pulse describes an interface that shows what is working and what is not.
folderly.com/email-deliverability-monitoring · read 22 October 2026
08
Alerts also named on the home page
The home page says Pulse gives alerts when it needs attention and that you get alerts when your inbox placement needs attention.
folderly.com · read 22 October 2026
09
Predictive analytics is mentioned, not described
The page's meta description mentions predictive analytics, but the page body does not describe it.
folderly.com/email-deliverability-monitoring · 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.
- How often Pulse checks
- Whether seed accounts are used
- Any usage limits on the free tier
- Setup steps, which the page does not list
- What an inbox rate threshold should be
- Whether alerts cover DNS or blocklist changes
- Whether a digest or per-event email is sent
Where the sources disagree
We report each version rather than pick one.
- The Pulse page names SMS only in a short phrase, Sync to email, SMS, Slack and more. Its body text lists email, Slack and other tools.
The numbers
Only what we could verify.
| Measure | Warmerly | Folderly |
|---|---|---|
| Alerts | An email digest, at most one a day; health webhooks on the Agency plan; no Slack alert found. | Pulse, listed as free, sends spam alerts by email, Slack and SMS or other tools. |
| Alert channels | Email, plus webhooks on Agency | Email, Slack, SMS and other tools |
| Emails a day | 1 digest a day at most | Not stated |
| Checks every | 15 minutes | Not stated |
| Kinds of alert | 7, none on placement | Placement, spam folder hits |
| Evaluations a day | 96 (every 15 minutes) | Not stated |
| Repeat of an unchanged problem | After 14 days | Not stated |
| Repeat of a new or worse fault | After 24 hours | Not stated |
| Grace for score alerts on a new mailbox | 14 days | Not stated |
| Webhook event types | 16, Agency plan | Not stated |
| Price of alerts | Email digest in the plan, webhooks on Agency | $0 for Pulse, as listed |
In practice
What it means for you.
Our reading of the facts above. Not a promise, and not the only reasonable reading.
If Slack matters, Folderly wins
Warmerly's alerts come by email, or by webhook on Agency, which you can route to Slack yourself.
Alerts do different jobs
Warmerly alerts on health, DNS and blocklists. Pulse alerts on placement.
A DNS record breaks on Monday
Warmerly's records sweep runs every six hours, so it is caught within 6 hours, then the digest follows within 24 hours. If you fix it before the digest, nothing is sent. Pulse alerts on placement, so a broken record would show only once mail starts landing in spam.
A fault nobody fixes
On Warmerly, the first alert goes out on day 0. If nothing changes, the next reminder waits 14 days, so at most 3 alerts over 28 days (day 0, 14 and 28).
Getting alerts into Slack
Folderly lists Slack as a channel. On Warmerly you would subscribe a relay of your own to a webhook on the Agency plan, using one of 16 event types.
A new mailbox that dips
A mailbox connected this week will not raise a score alert for 14 days, however far the score falls. If Pulse is on a new mailbox, its own page does not say whether it holds alerts back.
Who it suits
Pick the one that fits.
Warmerly
Warmerly is the better fit if
- Email is where you read alerts
- You want alerts on DNS and blocklist changes
- You want webhooks to route to your own tools
- You want alerts that stop repeating when nothing has changed
Folderly
Folderly is the better fit if
- You want alerts in Slack
- You want alerts on placement over time
- You want free real-time alerts
- You want a monitor built around an inbox rate you set
Questions
Does Folderly send Slack alerts?
Yes. Its Pulse page says spam alerts go through email, Slack (direct and channel messages) and other tools, and Pulse is listed as free (read 21 October 2026). Warmerly sends an email digest and webhooks on Agency, with no Slack alert.
Can Warmerly alert me on DNS changes?
Yes, by email digest, and by webhook on the Agency plan.
What does Warmerly alert on?
Health score falling 15 points or more, health below 50, a mailbox that loses its sign-in, DNS records changing, and domain or IP blocklistings. None of these is a placement alert.
Will Warmerly email me every day about the same problem?
No. An unchanged, unfixed problem waits 14 days before it is mentioned again, and the digest is at most one email per user per 24 hours.
Which events can I send to a webhook?
16 event types, such as score drop, score floor, auth fail, DNS changed, auto paused and aged in, on the Agency plan only. There is no blocklist event in the documented list.
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
- SPF, DKIM, DMARC and blocklist checks
- DMARC reports
- Inbox placement tests
- 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.