Email validation
Check addresses before they enter a send.
MailNox · Local-first cold email & marketing
The local-first desktop platform for cold email.
Warmup, campaigns, contacts, multiple senders, validation, deliverability and replies — all in one workspace.
Windows desktop · 64-bit installer
Campaign
Spring product launch
Status
Scheduled
Audience
1,240 eligible
Senders
4 identities
Replies
86
Needs reply
12
Follow-ups
9
Inbox
Maya Ellison
Re: Spring launch
Priya Mehta
Re: Product update
Daniel Reyes
Re: Q2 notes
The loop
Cold email shouldn't strand replies in another product.
Most outreach tools optimize for the send. MailNox connects the campaign to the real conversation — in the desktop inbox you already work from.
Each message is an individual email. When someone replies, the thread comes back to the mailbox you sent from.
- 01
Import & validate
CSV, groups, list hygiene
- 02
Warm up senders
Seed pool & controlled ramp
- 03
Build & personalize
Templates, merge, Spintax
- 04
Send across accounts
Adaptive pools & windows
- 05
Reply in your inbox
Real threads, not a silo
- 06
Follow up in-thread
Campaign context attached
MailNox vs cloud solution
Pricing that doesn't grow with your database.
Cloud outreach often meters contacts, sends, and mailboxes. MailNox keeps the core workspace local — so those aren't artificial tiers.
Capability
MailNox
Cloud solution
Architecture
Local-first desktop workspace
Cloud-first campaign platform
Everyday email
Full email client included
Usually outreach inbox only
Campaign replies
Your real MailNox inbox
Platform / outreach inbox
Stored contacts
Unlimited local storage
Often plan-limited
Connected mailboxes
Unlimited
Varies / sometimes metered
Monthly sends
No MailNox send quota
Frequently plan-limited
Email validation
2,500/month included
Credits or plan-dependent
Starting price
$29/mo or $290/yr
Often $39–$100+
Sending remains subject to provider limits and MailNox deliverability safeguards. Competitor plans change.
Everything in one desktop app
Cold email tools — plus the inbox those campaigns come back to.
Outreach & campaigns
Campaign wizard
Audience → content → senders → schedule → Validate & Preflight.
Templates & Spintax
Merge fields, Spintax, and on-device Generate Spintax.
Multi-account sending
Send from real mailboxes; replies return there.
Sender pools
Adaptive max/weight capacity you control.
Schedule & Adaptive Send
Windows, weekdays, finish-time estimates.
Warmup & seeds
Ramp new or cooled senders before volume.
Audience & compliance
Contacts & groups
CSV import, dedupe, targeted lists.
Email validation
Local checks or paid credit validation.
Suppression & unsubscribe
List hygiene and compliance footers.
Campaign preflight
Blockers for identity, list health, auth.
Deliverability & results
Auth & health
SPF, DKIM, DMARC, sender and domain health.
Bounce & complaints
Provider feedback before the next send.
Analytics
Sent through bounced — plus conversation state.
Inbox replies
Real threads with campaign context attached.
Desktop workspace
Multi-account inbox
Gmail, Microsoft, IMAP/SMTP in one client.
Views & labels
Organize outreach beside everyday mail.
People, tasks, calendar
Context next to the conversation.
Search & local AI
On-device find, summaries, Spintax drafts.
Campaigns
Build, schedule, and preflight in the same app as your inbox.
HTML or plain-text campaigns with templates, merge fields and Spintax. Walk the wizard through audience, content, senders, optional validation and warmup, schedule, then Review.
- Validate and Preflight before Start
- Templates, Spintax, Generate Spintax
- Preview per recipient and test send
- Sequences without leaving the desktop
- Send now, later, or Adaptive Send
Campaign preview · Maya Ellison
Hi {{first_name}},
{{I wanted to share|Thought you might be interested in|A quick note about}} the spring launch.Individual message
Hi Maya,
I wanted to share the spring launch.
One recipient · own unsubscribe · replies thread normally
Contacts & validation
Import, clean, and qualify before you send.
CSV, groups, validation, and suppression beside your campaigns — a lightweight contact workspace, not a separate CRM.
- CSV import with deduplication
- Contact groups for targeted audiences
- Local checks or paid validation credits
- Eligibility and lawful-basis attestation
- Suppression, unsubscribe, campaign history
Spring audience
1,240 eligible · 86 suppressed
Product launch
640 eligible
Customers
418 eligible
Suppressed
86 held
CSV import, deduplication, eligibility and campaign history stay with the contact.
Sender identities
One campaign. Multiple real mailboxes.
Pool the accounts you already use. Adaptive distribution respects per-sender, provider, and domain limits — replies land in those same inboxes.
- Single sender or Adaptive pool
- Max, weight, and capacity you control
- Provider and domain-aware limits
- Finish-time estimate from caps and windows
- Health and warmup state per identity
Sender pool · Spring launch
Eligible recipients distributed across approved identities.
hello@northwind.io
Ready80 / day
maya@northwind.io
Ready40 / day
team@harborline.co
LimitedDomain cap
Sending & scheduling
Send now, later, or across accounts.
Adaptive Send is capacity management across your pool — volume ramps with reputation, not against it.
Send now
Start immediately through approved sender identities.
Schedule
Choose send windows and weekdays before volume leaves.
Adaptive Send
Distribute across the pool with caps, limits, and a finish-time estimate.
Warmup
Protect reputation before you scale.
Low-volume seed traffic warms new or cooled mailboxes before cold or marketing volume.
Diverse seed pool
Primary, secondary, and reply-capable seeds across providers.
Controlled ramp
Per-sender caps and streak progress before heavy volume.
Optional campaign gate
Require warmup-ready senders — or skip when you accept the risk.
Deliverability
Know before you send.
Validation, authentication, suppression, warmup readiness, and preflight. MailNox respects provider limits — it does not guarantee inbox placement.
Sender health
See which identities are ready to carry volume.
Domain health
Review domains behind your sender pool.
SPF / DKIM / DMARC
Confirm authentication before Start.
Suppression
Keep suppressed addresses out of the next send.
Unsubscribe
Honor recipient-specific unsubscribe requests.
Bounce monitoring
Watch bounces as they return from the provider.
Complaint signals
Notice complaints before the next campaign.
Campaign preflight
Review readiness before you send or schedule.
Warmup readiness
See who is ready — or still warming.
Postal & unsubscribe
Compliance identity and footer injection.
List health
Catch invalid or ineligible addresses early.
Conversations
Campaign replies belong in your real inbox.
When someone replies, MailNox treats it as a normal email conversation — not a separate outreach silo. Campaign context stays attached.
- Campaign name and ID on the thread
- Original send time and subject
- Sender identity that went out
- Recipient and group context
- Pause, end, or clone from My Campaigns
Inbox · campaign replies
Same mailbox as everyday email.
Needs reply
Maya Ellison — Spring launch
Sender hello@northwind.io · Product launch
Follow-up due
Priya Mehta — Product update
Sent Tuesday · Campaign spring-launch
Question open
Daniel Reyes — Q2 notes
Group Customers · original subject retained
Analytics
See the campaign. Then the conversation.
Track sends through bounces, then continue every reply in the same inbox. Open and click tracking is optional via MailNox Cloud.
Campaign
- Sent
- Delivered
- Opened
- Clicked
- Replied
- Unsubscribed
- Bounced
Conversation
- Needs Reply
- Follow-up Due
- Waiting
- Positive Replies
- Active
Desktop email workspace
Outreach on top of a full email client.
Not a thin campaign overlay — multi-account mail, views, people, tasks, search, and on-device intelligence share one local-first desktop.
Workspace
- Unified inbox across Gmail, Microsoft, and IMAP/SMTP
- Custom views and labels
- People, tasks, and attachments beside mail
- Needs-attention triage for what still needs a reply
From conversation to work
TaskSend revised implementation estimate
OwnerYou
Due dateFriday
PriorityHigh
SourceMaya Ellison / Harborline estimate
StatusWaiting on you
Local AI
- Summarize campaign replies and long threads
- Surface unanswered questions and commitments
- Generate Spintax in the template editor
- Optional cloud models only when you choose them
Campaign replies
18 replies on Spring launch. 12 still need a response.
Unanswered
Maya asked whether the launch includes the agency tier.
Commitment
You offered Priya a follow-up after the webinar.
Needs attention
Three conversations have been waiting more than two days.
Search
On-device full-text search across multi-account mailboxes — including threads that started as cold outreach.
Find the conversation, not just the keyword
Remember the idea
- emails about the payment issue with Harborline
- the quote Maya sent last month
- messages where I promised to follow up
- threads waiting for my response
Local-first
Your cold email workspace doesn't need to live in someone else's cloud.
Mailbox, contacts, campaigns, templates, search, and supported AI stay on your device. Cloud is only for public endpoints — unsubscribe and optional tracking.
Mail stays local
Downloaded messages and mailbox state remain on-device where supported.
Contacts stay local
Working contact database and groups stay on your machine.
Campaigns stay local
Drafts, recipient assignments, templates, and local queues.
AI can stay local
Supported intelligence — including Generate Spintax — may run on-device.
Who it's for
Built for teams who live in email.
Digital marketers
Campaigns and replies in one client.
Create campaigns, manage contacts, schedule sends and handle replies without switching tools.
Agencies
Client campaigns without another system of record.
Multiple client mailboxes, sender identities and campaigns from one local-first desktop.
Growth teams
Keep every response tied to the send.
Targeted campaigns with sender, group and campaign context on every reply.
Small marketing teams
Campaign tools without a heavyweight platform.
Contacts, campaigns, deliverability and reply handling — no separate marketing suite.
Founders & operators
Outreach beside everyday email.
Send targeted campaigns while managing business email in the same application.
What is MailNox?+
MailNox is a local-first desktop app for cold email and email marketing. It combines everyday email, campaigns, contacts, validation, warmup, multi-account sending, deliverability checks, analytics and campaign replies in one workspace.
Is MailNox a cold-email tool or a Mailchimp replacement?+
MailNox is built for cold outreach and marketing campaigns from your real mailboxes — not a mass ESP or full marketing-automation suite. Prospecting, follow-up, and list-based campaigns are first-class; everyday email stays in the same app.
Where do campaign replies go?+
Replies return to the normal MailNox inbox as real email conversations. Campaign name, sender identity, recipient, group and original subject stay attached so you can continue the thread.
Can one campaign use more than one sender?+
Yes. A campaign can use multiple approved sender identities. Adaptive Send distributes eligible recipients across that pool while respecting per-sender, provider and domain limits, with a finish-time estimate on the Senders step.
Does MailNox include warmup and email validation?+
Yes. Warmup uses a diverse seed pool to ramp senders before heavy volume. Email validation offers quick local checks and optional paid credits; suppression and unsubscribe keep lists clean.
Does my campaign data stay on my device?+
Mailbox data, contacts, campaign drafts, templates, search and supported AI stay local to your device. MailNox Cloud is used only for features that need a public endpoint, such as unsubscribe and optional open or click tracking.
Does MailNox guarantee inbox placement?+
No. MailNox helps you check validation, authentication, suppression, warmup readiness, bounces and campaign preflight before you send. It respects provider limits and does not promise inbox placement.
Who is MailNox for?+
Marketers, agencies, growth teams, founders and operators who run cold or marketing outreach and want replies in the same desktop inbox they work from every day.
Do I have to change my email address?+
No. MailNox connects to the email accounts you already use and sends campaigns through those sender identities.
Get MailNox
Your inbox. Your outreach. Your data.
Cold email and marketing from a local-first desktop — campaigns, contacts, multi-account sending, deliverability, and every reply in one place.