Warmerly
On every mailbox, threaded warmup emails with automated, quoted replies
Warmerly
Smartlead
One-to-one · Warmup
Warmup
One row, in depth: what each tool does, the verified numbers, and who each suits.
Smartlead details read from its pricing page, home page and help centre on 17 and 19 October 2026.
Warmerly
On every mailbox, threaded warmup emails with automated, quoted replies
Smartlead
Built-in warm-up with its own pool
The short answer
Warmup, in one look.
Both run warmup through a pool of real mailboxes that open, reply and rescue mail from spam. Smartlead lets you set the volume, ramp and reply rate yourself and does not limit how many mailboxes you warm. Warmerly fixes the ramp (4 a day at the start, 50 by day 30, lower for Gmail and Outlook), shows why today's limit is what it is, and limits mailboxes by plan (5, 25 or 100). Smartlead's own pages disagree with each other on the recommended daily volume, so check the in-app guidance before you copy a number. Last checked 19 October 2026.
Smartlead
Built-in warm-up with its own pool
The picture
Drawn side by side.
The ramp, drawn
Emails a day per mailbox over the first 30 days. Pick a Warmerly mailbox type.
WarmerlySmartlead
- Warmerly: anchor points from its warmup code, drawn straight between them. Provider caps and the 0.6 weekend factor are applied exactly as the code does, rounding aside.
- Smartlead: the three values in its API guide timeline, with the stable band and the maintenance band it describes. Between those points the guide does not say, so the line is only a join.
| Source | Point | Emails a day |
|---|---|---|
| Warmerly | Day 0 | 4 |
| Warmerly | Day 3 | 8 |
| Warmerly | Day 7 | 15 |
| Warmerly | Day 14 | 25 |
| Warmerly | Day 21 | 35 |
| Warmerly | Day 30 | 50 |
| Warmerly | Gmail cap, reached at day 24 | 40 (24 at the weekend) |
| Warmerly | Outlook cap, passed at about day 18 | 30 (18 at the weekend) |
| Warmerly | Zoho cap, reached at day 14 | 25 (15 at the weekend) |
| Warmerly | Ceiling for any mailbox, day 30 | 50 (30 at the weekend) |
| Smartlead API guide | Day 1 | About 5 |
| Smartlead API guide | Day 7 | About 19 |
| Smartlead API guide | Day 14 | 33 or more |
| Smartlead API guide | Stable, day 14 onwards | 33 to 40 |
| Smartlead API guide | Maintenance, alongside campaigns | 15 to 25 |
Smartlead's timeline climbs faster early on (about 19 a day on day 7, against 15 for Warmerly) and its guide says 33 to 40 from day 14. Warmerly reaches a higher ceiling of 50, but not until day 30, and lower for Gmail, Outlook and Zoho. Both are recommendations or limits for warmup mail only, not promises of inbox placement.
One question, several answers
Daily warmup emails per mailbox, as each company's own pages give them. Same axis on both sides.
WarmerlySmartlead
WarmerlyWhat the code does
- Ramp, day 0 to day 30Warmerly code: 4 a day rising to 504 to 50
- Gmail mailbox at its capReached at day 2440
- Outlook mailbox at its capPassed at about day 1830
- Zoho mailbox at its capReached at day 1425
- Weekend, mailbox on the 50 ceiling50 x 0.630
SmartleadWhat its pages recommend
- Help centre, while a campaign runsWarm-up help article10 to 20
- total_warmup_per_dayAPI guide recommendation20 to 40
- Stable, from day 14API guide timeline33 to 40
- Maintenance, alongside campaignsAPI guide timeline15 to 25
- Google mailbox bought via SmartSendersSmartSenders FAQ, InboxAutomate20 to 30
- Google mailbox via ZapmailSmartSenders FAQ, for 2 weeks25
- Outlook mailbox via InfraInboxSmartSenders FAQ: 10 to 15, up to 20, never beyond10 to 20
| Company | Source and case | Emails a day |
|---|---|---|
| Warmerly | Ramp, day 0 to day 30 | 4 to 50 |
| Warmerly | Gmail cap | 40 |
| Warmerly | Outlook cap | 30 |
| Warmerly | Zoho cap | 25 |
| Warmerly | Weekend, on the 50 ceiling | 30 |
| Smartlead | Help centre, while a campaign runs | 10 to 20 |
| Smartlead | API guide, total_warmup_per_day | 20 to 40 |
| Smartlead | API guide, stable from day 14 | 33 to 40 |
| Smartlead | API guide, maintenance | 15 to 25 |
| Smartlead | SmartSenders FAQ, Google (InboxAutomate) | 20 to 30, reply rate 65 to 75 per cent |
| Smartlead | SmartSenders FAQ, Google via Zapmail | 25, reply rate 60 to 75 per cent |
| Smartlead | SmartSenders FAQ, Outlook via InfraInbox | 10 to 15, rising to 20 and never beyond |
Warmup and campaign sends on one mailbox
Smartlead shares one daily limit. Warmerly keeps two separate settings.
WarmerlySmartlead
Warmerly
Two settings. Warmup follows its own ramp. A campaign has its own daily limit, 30 by default. One does not shrink the other, but the mailbox does both jobs on the same day.
Smartlead
0max_email_per_day 40, Smartlead's own example
One limit, shared. The API guide says warmup volume falls as campaign sends rise and ramps back up when they fall. The split above is its published example.
Both bars use the same 0 to 50 scale. The Smartlead split is an example from its API guide, not a default. Warmerly's 50 is the ceiling of the ramp, reached at day 30, and the 30 is the default campaign limit.
On screen
What it looks like.
WarmerlySample data
How Warmerly does it
Warmerly, in detail.
A fixed 30-day ramp per mailbox, with provider ceilings, health-based reductions and a visible reason for each day's limit. Warmup sends are not metered, and the number of mailboxes is limited by plan.
01
The ramp is set by us, not by a slider
The daily quota is interpolated between anchor points: 4 a day at day 0, 8 at day 3, 15 at day 7, 25 at day 14, 35 at day 21 and 50 at day 30. It counts days on which the mailbox really sent, so a paused or newly enabled old mailbox cannot skip ahead. Domain age is not an input.
Warmerly product, checked 19 October 2026
02
The ceiling is the lowest of three limits
The quota is the lowest of the age ramp, the provider cap and the hard ceiling of 50 a day. Provider caps are Gmail 40, Outlook 30 and Zoho 25. Working it through the ramp: a Zoho mailbox hits its cap of 25 at day 14, an Outlook mailbox passes 30 at about day 18 (the ramp is 29 on day 17 and 31 on day 18), and a Gmail mailbox passes 40 at day 24 (35 at day 21 plus a third of the 15 between day 21 and day 30).
Warmerly product, checked 19 October 2026
03
Weekends and health cut the quota further
Weekends run at 0.6 of the weekday quota, measured in the mailbox's own timezone, so a mature mailbox on the 50 ceiling plans 30 on a weekend (50 x 0.6), a mature Gmail mailbox 24 (40 x 0.6), Outlook 18 (30 x 0.6) and Zoho 15 (25 x 0.6). A spam placement score of 20 or more multiplies the quota by 0.4, 10 or more by 0.7. A health score below 50 multiplies it by 0.4, below 70 by 0.75. The lower of the two reductions applies. You can also set a lower daily warmup limit on a mailbox. The reply probability is not a setting: it starts at 0.3 and the product tunes it between 0.15 and 0.40 by the mailbox's health.
Warmerly product, checked 19 October 2026
04
The reason for today's limit is named
The capacity calculation returns a named limiting factor for every mailbox (age, provider, hard cap, health, weekend, your own daily limit, paused and others), and the warmup page in the app reads it. A mailbox whose sends were refused gets one send a day, not zero, so it can recover or reach the pause that asks you to reconnect. Free sandbox mailboxes are capped at 3 a day.
Warmerly product, checked 19 October 2026
05
What each warmup message does
A warmup mail is opened after a delay of 10 to 120 minutes, about 90 per cent of ordinary mail is opened, about 20 per cent of opened mail is starred as important, and the recipient replies with a default probability of 0.3 on a first message, stopping at thread depth 3. Spam-placed mail is different: every message is read, moved to the inbox and answered.
Warmerly product, checked 19 October 2026
06
A peer pool, with terms
Warmup mail is real mail between mailboxes in one pool. The Warmup Network Participation Terms say the pool includes other customers' mailboxes and may include mailboxes Warmerly hosts or operates. The planner picks each recipient by spreading load, mixing providers and how that recipient's domain has treated the sender over the last 14 days. A sender does not write to the same recipient twice within 72 hours (relaxing to 48 then 24 if the pool runs short).
Warmerly product, checked 19 October 2026
07
Not metered, but not unlimited
Warmup sends are not a billing meter on paid plans, but every mailbox follows the ramp and ceiling above. The limit you feel is the number of mailboxes: 1 on Free, 5 on Starter, 25 on Growth and 100 on Agency, with more on a call.
Warmerly product, checked 19 October 2026
08
Warmup and campaigns have separate limits
A mailbox's warmup quota comes from the ramp above. A campaign has its own daily limit, 30 by default. The two are separate settings, so one does not shrink the other, but the mailbox does both jobs on the same day.
Warmerly product, checked 19 October 2026
How Smartlead does it
Smartlead, in detail.
Warmup with settings you control (daily volume, ramp, randomisation, reply rate), on every plan, for unlimited mailboxes. Its help centre, API guide and SmartSenders FAQ each give different recommended numbers.
01
No mailbox limit
Smartlead's pricing page says all plans include unlimited email accounts at no extra cost. The plans are limited by emails a month and contacts instead (Base $39: 6,000 emails and 2,000 contacts; Pro $94: 90,000 and 30,000). The features grid has a 'Warmup Pool' row, but its per-plan ticks are images and could not be read.
smartlead.ai/pricing · read 19 October 2026
02
Settings you choose
The help article lists total daily emails, a daily ramp-up (for fresh domains, not for domains already warmed or moved from another tool), randomised warmup numbers within thresholds you set, and a reply rate. It says to keep daily warmup to 10 to 20 for an account running an active campaign, and calls a 20 to 30 per cent reply rate healthy, with above 30 not recommended unless you are an expert. It gives no maximum daily volume and no ramp increments.
helpcenter.smartlead.ai/en/articles/52-how-to-enable-ai-email-account-warm-ups · read 19 October 2026
03
The API guide gives a timeline
The API guide recommends total_warmup_per_day of 20 to 40 (not above 40 for new accounts), a daily ramp-up of 2 to 3 and a reply rate of 30 to 40 per cent. It describes days 1 to 7 as 5 rising to 19 emails a day, days 8 to 14 as 20 rising to 33, then 33 to 40, and 15 to 25 a day for ongoing maintenance. It suggests 14 or more days of uninterrupted warmup (21 to 30 for newer domains) and inbox placement above 90 per cent before campaigns.
api.smartlead.ai/guides/email-warmup · read 19 October 2026
04
Warmup shares the mailbox's daily limit with campaigns
The API guide says Smartlead coordinates warmup and campaign sends within the mailbox's max_email_per_day, for example 40 in total as 15 warmup and 25 campaign, and that warmup volume decreases as campaign sends increase and ramps back up when they fall. It says to keep warmup on after campaigns start, and to cut total_warmup_per_day to 10 and rebuild gradually if warmup emails land in spam.
api.smartlead.ai/guides/email-warmup · read 19 October 2026
05
Advice for bought mailboxes differs by provider
The SmartSenders FAQ gives separate warmup advice per provider. Google mailboxes (InboxAutomate): 20 to 30 warmup emails a day at a 65 to 75 per cent reply rate, ramping 2 to 4 a day. Google via Zapmail: 25 a day at a 60 to 75 per cent reply rate for 2 weeks. Outlook (InfraInbox): 14 days of warmup, then 10 to 15 a day ramping to 20, never beyond. Mailreef SMTP: at least 14 days, ideally 30 or more, with 20 cold and 20 warmup emails a day when fully warmed.
helpcenter.smartlead.ai/en/articles/256-smartsenders-faqs-and-troubleshooting-everything-you-need-to-know · read 19 October 2026
06
Pool and protection
The help article describes a pool of aged, high-reputation domains across Zoho, Gmail, Outlook and others, and says accounts with bounce problems are automatically delisted from the warmup pool. The API guide says the pool has 'thousands of email accounts'. The home page calls it a reward-based, limited-access network and says Smartlead handles DNS, warm-ups and sender rotation automatically. No pool size or vetting is given.
helpcenter.smartlead.ai/en/articles/52-how-to-enable-ai-email-account-warm-ups · read 19 October 2026
07
SmartAssistant reviews your warmup
Smartlead's SmartAssistant checks whether warmup is enabled, the current ramp-up pace, inbox against spam placement ratios, and whether daily limits match the warmup stage. It flags sending that is too aggressive for the warmup age, and its own example warns that a warmup of 6 days needs 4 to 6 weeks before heavy sending. It covers 28 diagnostic types across 14 categories.
helpcenter.smartlead.ai/en/articles/451-diagnosing-problems-with-smartassistant · read 19 October 2026
08
Pre-warmed mailboxes you can buy
SmartSenders sells fresh and pre-warmed Google and Outlook mailboxes. The pricing page lists pre-warmed Google or Outlook mailboxes (Zapmail) at $18 a domain a year and $9 a mailbox a month, against $13 a domain a year and $4.5 a mailbox a month for fresh ones. SmartSenders says pre-warmed mailboxes skip the 2 to 3 week warmup. Its FAQ says a standard mailbox still needs warmup.
smartlead.ai/pricing · read 19 October 2026
What Smartlead does not say
We looked, and found no statement on these. That is about its published pages only, not about the product.
- A maximum value for the daily warmup setting, the ramp-up increment schedule, the randomisation thresholds and the pool size are not given in the help article.
- The warmup settings page of Smartlead's API reference was seen only through a search summary, not read in full, so its ranges are not used here.
- Which plans include warmup and the Warmup Pool row: the pricing page ticks are images and could not be read.
- The Smartlead 101 module on how email warmup works promises realistic timelines, but its page gives no day counts, ramp figures or progress benchmarks.
- No official Smartlead video on warmup could be confirmed, so none is shown here.
The numbers
Only what we could verify.
| Measure | Warmerly | Smartlead |
|---|---|---|
| Warmup | On every mailbox, threaded warmup emails with automated, quoted replies | Built-in warm-up with its own pool |
| Mailboxes warmed on the starting plan | 5 (Starter, $19 a month) | Unlimited accounts (Base, $39 a month) |
| Warmup volume you set yourself | A lower daily limit per mailbox; the ramp and reply rate are fixed | Total daily emails, ramp-up, randomisation and reply rate |
| Day-one volume | 4 a day | 5 a day in the API guide's timeline; help centre gives no figure |
| Volume at day 7 | 15 a day | About 19 a day (API guide) |
| Volume at day 14 | 25 a day | 33 or more a day (API guide) |
| Daily volume at maturity | 50 by day 30 (Gmail 40, Outlook 30, Zoho 25) | 33 to 40 from day 14, then 15 to 25 for maintenance (API guide); help centre says 10 to 20 while campaigns run |
| Reply rate | Default 0.3 on a first message, tuned by health, not a setting | 20 to 30 per cent (help centre) or 30 to 40 per cent (API guide) |
| Warmup counted with campaign sends | Separate: warmup follows its own quota and campaigns have their own daily limit (30 by default) | Shared inside max_email_per_day; warmup falls as campaigns rise |
| Weekend volume | 0.6 of the weekday quota | Not stated |
| When health drops | Quota cut automatically (x0.4 to x0.75) | API guide advises cutting total_warmup_per_day to 10 by hand; accounts with bounce problems are delisted from the pool |
| Time before sending campaigns | 30-day ramp to the ceiling | 14 or more days, 21 to 30 for newer domains (API guide) |
| Pool size published | Not published | 'Thousands of email accounts' (API guide) |
In practice
What it means for you.
Our reading of the facts above. Not a promise, and not the only reasonable reading.
Our reading: Smartlead is the more adjustable tool
If you want to choose volume, ramp and reply rate yourself, or warm a very large fleet, Smartlead's settings and unlimited accounts fit better. Warmerly's ramp is fixed on purpose, and that suits people who would rather not tune it.
Our reading: Smartlead's published ramp climbs faster
On the API guide's timeline a mailbox is at about 19 a day by day 7 and 33 or more by day 14. Warmerly is at 15 and 25 on the same days, and reaches its ceiling of 50 at day 30. Which is better depends on how fast you want to send, and neither is a promise of inbox placement.
Our reading: Smartlead's pages give several different answers
The help article says 10 to 20 a day during a campaign, the API guide says 20 to 40, and the SmartSenders FAQ says 20 to 30 for a Google mailbox or 10 to 15 for Outlook. All are recommendations, not limits. We would test a small number of mailboxes before copying any of them.
Our reading: the shared limit changes how you plan
On Smartlead a busy campaign reduces warmup on the same mailbox. On Warmerly warmup and campaign sends have separate settings, which is simpler to reason about but means a mailbox does both jobs at once.
Our reading: a fixed ramp trades control for fewer decisions
Warmerly lowers the quota for you at weekends, when health drops or when a provider cap applies, and names the reason. Smartlead gives you the dials and the advice. If you do not want to watch a dashboard daily, the first is less work. If you want to push a mailbox harder, the second lets you.
Our reading: both are peer pools
Neither company publishes how its pool is vetted. Warmerly's terms say the pool includes other customers' mailboxes, and Smartlead describes a limited-access network. Ask either vendor before you rely on pool quality.
Our reading: buying pre-warmed mailboxes is a different route
Smartlead can sell you mailboxes that skip the 2 to 3 week warmup. That is not the same job as warming mailboxes you already own, and it costs $9 a mailbox a month on top of the plan.
Who it suits
Pick the one that fits.
Warmerly
Warmerly is the better fit if
- You want a fixed, visible ramp and the reason for today's limit, without tuning settings.
- You have between one and 100 mailboxes and want a flat price with no email or contact meter.
- You want warmup that can run on its own while you send from another tool.
Smartlead
Smartlead is the better fit if
- You want to set daily volume, ramp-up, randomisation and reply rate yourself.
- You run a very large or fast-growing fleet and do not want a mailbox limit.
- You want to buy pre-warmed mailboxes through SmartSenders instead of warming your own.
Questions
Can I set my own warmup volume?
On Smartlead, yes: total daily emails, ramp-up, randomisation and reply rate. On Warmerly the ramp and reply rate are fixed, and you can only lower the daily limit.
What is Warmerly's ramp?
4 a day on day one, 15 at day 7, 25 at day 14 and 50 by day 30. Provider ceilings are Gmail 40, Outlook 30 and Zoho 25.
What does Smartlead recommend?
Its API guide shows 5 a day on day one, about 19 at day 7 and 33 or more at day 14. Its help centre says 10 to 20 while campaigns run, so its pages disagree.
How many mailboxes warm up?
Smartlead warms unlimited accounts on Base at $39. Warmerly warms the 5, 25 or 100 mailboxes its plan covers.
Sources
- Smartlead pricing (read 2026-10-19)
- Smartlead home page (read 2026-10-19)
- Smartlead help: enable AI warmups (read 2026-10-19)
- Smartlead API guide: email warmup (read 2026-10-19)
- Smartlead help: SmartSenders FAQs and troubleshooting (read 2026-10-19)
- Smartlead help: diagnosing problems with SmartAssistant (read 2026-10-19)
- Smartlead SmartSenders (read 2026-10-19)
- Smartlead 101: how email warmup works (read 2026-10-19)
Smartlead pages were read on 19 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)
- Mailboxes on the starting plan
- Most mailboxes on a published price
- Emails per month on the starting plan
- Highest published send volume
- Contacts on the starting plan
- Spam-folder rescue
- SPF, DKIM and DMARC monitoring
- Inbox placement testing
- Built-in campaign sender
- Shared reply inbox
- LinkedIn steps in the same sequence
- Ready-made mailboxes
- Agency and white-label
- Integrations
- API
- Free plan or trial
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.