# Zylar

> Zylar is a cold email sequencer built by cold emailers. It runs AI on every layer (copy, replies, follow-ups, A/B winners) and manages the infrastructure most teams struggle with: domain DNS checks, warm-up, inbox rotation, placement testing and automatic pausing of domains that slip. Zylar is currently in early access via a waitlist.

Key facts:
- Pricing is by emails sent, not seats or inboxes. Every plan includes unlimited inboxes, seats, campaigns and workspaces. Warm-up is free and never counts toward sends.
- Plans (monthly):
  - Growth: $97, 150,000 emails/mo
  - Scale: $197, 300,000 emails/mo
  - Agency: $397, 500,000 emails/mo, with dedicated IP pools, white-label and private Slack support
  - Enterprise: custom, 1M+ emails/mo, private cluster
  - Yearly billing gives 2 months free.
- Email verification (EmailShield) and enrichment (LeadSonar) credits are bundled in every plan. Inboxes (Maildeck) are an add-on.
- Deliverability is on by default:
  - SPF, DKIM and DMARC are checked when you connect a domain.
  - Private warm-up pool of real inboxes.
  - Rotation, daily caps and time-zone windows.
  - Gmail and Outlook placement tests per domain and a daily inbox health score.
  - Domains auto-pause when placement drops.
- Unibox: one inbox for all replies across mailboxes and client workspaces, with AI interest labels.
- Integrations: HubSpot, Slack, Microsoft Teams, Zapier, Make, webhooks, REST API, and an MCP server so AI agents (Claude, ChatGPT, Cursor) can run campaigns.

## Product

- [Home](https://zylar.io/): overview
- [Features](https://zylar.io/features): sequencer, AI, Unibox, workspaces
- [Deliverability](https://zylar.io/deliverability): the four deliverability layers
- [Pricing](https://zylar.io/pricing): plans and what's included
- [Inboxes & warm-up](https://zylar.io/features-inboxes)
- [Sequences](https://zylar.io/features-sequences)
- [Unified inbox](https://zylar.io/features-unified-inbox)
- [Analytics](https://zylar.io/features-analytics)
- [For agencies](https://zylar.io/use-cases-agencies)
- [For founders](https://zylar.io/use-cases-founders)
- [Integrations](https://zylar.io/integrations)
- [Free tools](https://zylar.io/free-tools): SPF/DKIM/DMARC checker
- [Join the waitlist](https://zylar.io/signup)

## Docs

- [Introduction to Zylar](https://zylar.io/docs/introduction): What Zylar is and how its core concepts fit together, from workspaces, domains and inboxes to warm-up, sequences, leads and the Unibox for replies.
- [Quickstart](https://zylar.io/docs/quickstart): The end-to-end path in Zylar, from creating a workspace and connecting a domain to warming inboxes, adding leads and launching your first sequence.
- [Connect a domain](https://zylar.io/docs/connect-a-domain): What Zylar checks when you connect a sending domain (SPF, DKIM, DMARC, tracking domain, MX), how to fix issues, and example records for Google and Microsoft.
- [Warm-up](https://zylar.io/docs/warm-up): How Zylar warms inboxes through a private pool of real inboxes on a ramp schedule, why it's free on every plan, and why warm-up never counts toward your sends.
- [Sending and rotation](https://zylar.io/docs/sending-and-rotation): How Zylar sends campaign email: rotation across inboxes, daily caps per inbox, random gaps between sends and sending windows in each lead's time zone.
- [Monitoring and auto-pause](https://zylar.io/docs/monitoring-and-auto-pause): How Zylar monitors deliverability with Gmail and Outlook placement tests and a daily 0–100 inbox health score, and what auto-pause does when placement drops.
- [Sequences](https://zylar.io/docs/sequences): How Zylar sequences work: multi-step campaigns with delays, AI-written copy, personalization, spintax, A/B/C tests with auto-promoted winners and follow-ups.
- [Leads](https://zylar.io/docs/leads): How to add leads to Zylar sequences, which fields a lead has, how duplicates and blocklisted addresses are skipped, lead statuses, verification and enrichment.
- [Unibox](https://zylar.io/docs/unibox): How the Zylar Unibox collects replies from every inbox and client into one list, labels them by intent, and lets you reply, assign or push leads to HubSpot.
- [Workspaces and roles](https://zylar.io/docs/workspaces-and-roles): How Zylar workspaces isolate each client's data, why workspaces and teammates are unlimited, how roles go down to client view-only, and what Agency adds.
- [API reference](https://zylar.io/docs/api): The Zylar REST API v1: base URL, bearer authentication, rate limits and errors, plus every endpoint for leads, sequences, inboxes, stats and webhooks.
- [Webhooks](https://zylar.io/docs/webhooks): Zylar webhook events, how to subscribe an HTTPS endpoint, how to verify the X-Zylar-Signature HMAC-SHA256 header in Node.js and Python, and how retries work.
- [MCP server](https://zylar.io/docs/mcp): What the Zylar MCP server does: it lets AI assistants such as Claude, ChatGPT and Cursor read and run your cold email campaigns. Included on every plan.
- [Integrations](https://zylar.io/docs/integrations): The tools Zylar connects to: Gmail, Outlook and SMTP/IMAP inboxes, HubSpot, Slack, Teams, Zapier, Make, Google Calendar, Zoom, webhooks, the REST API and MCP.
- [Plans and billing](https://zylar.io/docs/plans-and-billing): Zylar plans and pricing: monthly email volumes, what counts as a send, free warm-up, yearly billing with 2 months free, credits, infrastructure and add-ons.

## Blog

- [How to recover a burned cold email domain](https://zylar.io/blog/burned-domain-recovery): To recover a burned cold email domain, stop sending, check blocklists and Postmaster Tools, fix the root cause and ramp slowly, or retire the domain. (by Nikita Stoletov)
- [Running cold email for 20 clients without losing track](https://zylar.io/blog/cold-email-agency-operations): To run cold email for 20 clients, give each a workspace, name domains and inboxes consistently, keep an infrastructure ledger and report weekly. (by Levi Nagy)
- [What cold email really costs in 2026: inboxes, domains and tools](https://zylar.io/blog/cold-email-cost-breakdown): Real 2026 cold email costs by inbox type: Google $2–3/inbox, Outlook $0.30–0.40, SMTP $0.50–0.99. A 100k/month stack runs about $360 in inboxes. (by Sabo Nagy)
- [Cold email infrastructure: the complete setup checklist (and what to automate)](https://zylar.io/blog/cold-email-infrastructure-checklist): The cold email infrastructure checklist: domains, redirects, inboxes, SPF/DKIM/DMARC, tracking, warm-up, rotation, monitoring, and which steps to automate. (by Sabo Nagy)
- [Why cold email lands in Outlook junk (and how to fix it)](https://zylar.io/blog/cold-email-outlook-junk): Cold email lands in Outlook junk because of failed authentication, bulk-style signals and tenant filters. Fix DMARC alignment, links, volume and test placement. (by Nikita Stoletov)
- [Email warm-up for cold email: what it does, and why yours isn't working](https://zylar.io/blog/email-warm-up-guide): Email warm-up builds sending history for new inboxes, but can't fix bad lists, broken auth or spammy copy. Warm-up times by inbox type, and what to check first. (by Nikita Stoletov)
- [Gmail, Yahoo and Microsoft bulk sender rules: what cold emailers must do in 2026](https://zylar.io/blog/gmail-yahoo-microsoft-bulk-sender-rules): Gmail, Yahoo and Microsoft require bulk senders to use SPF, DKIM, aligned DMARC, one-click unsubscribe and keep spam under 0.3%. What cold email must do. (by Nikita Stoletov)
- [How many domains and inboxes do you need for cold email?](https://zylar.io/blog/how-many-inboxes-cold-email): Inboxes needed = daily sends ÷ the per-inbox rate for your inbox type (Google 15–20, Outlook 3–10, SMTP 11–14). 150k a month takes about 770 inboxes on 59 domains. (by Sabo Nagy)
- [Instant domain swap: replace a burned cold email domain without losing a send](https://zylar.io/blog/instant-domain-swap): When a cold email domain burns, the fix usually costs days of lost sends and manual inbox shuffling. Here's the manual process, and how an instant domain swap removes it. (by Sabo Nagy)
- [How to set up SPF, DKIM and DMARC for cold email](https://zylar.io/blog/spf-dkim-dmarc-cold-email): Set up SPF, DKIM and DMARC for cold email with one SPF record under 10 lookups, 2048-bit DKIM, and DMARC at p=none with reports before quarantine. (by Nikita Stoletov)
- [The 3-step cold email sequence we'd send tomorrow](https://zylar.io/blog/three-step-cold-email-sequence): A 3-step cold email sequence template: a short intro with one ask, a value-adding follow-up in the same thread, and a polite last touch, plus timing and subject lines. (by Sabo Nagy)

## Authors

- [Sabo Nagy](https://zylar.io/authors/sabo-nagy): Founder & CEO, MailDeck. Has built email infrastructure serving 1M+ inboxes across 1,500 clients. Specializes in email infrastructure strictly for high-volume cold outreach.
- [Nikita Stoletov](https://zylar.io/authors/nikita-stoletov): CTO, MailDeck · Outbound Infrastructure & Deliverability Engineering. CTO designing cold email infrastructure and outbound systems at scale. Built and managed infrastructure delivering over 50M emails monthly across 1,200+ domains with 98% inbox placement.
- [Levi Nagy](https://zylar.io/authors/levi-nagy): Head of Operations & Client Success, MailDeck. Manages end-to-end client onboarding and infrastructure deployment at MailDeck. Oversees delivery of 1M+ inboxes and ensures seamless integration for high-volume outbound teams.

## Optional

- [Full text of all docs and posts](https://zylar.io/llms-full.txt)