GMass vs Warmy: Cold Email Platform vs Email Warmup Tool Comparison
Compare GMass (cold email platform) and Warmy (email warmup tool) side by side. See pricing, features, and integrations to decide which one, or both, your stack needs.
GMass is a Gmail-based cold email platform starting at $29.95 a month, built for sending mail-merge campaigns, automated follow-ups, and A/B tests directly inside Gmail. Warmy is an email warmup and deliverability tool with custom, contact-sales pricing that warms domains and IPs using seed lists, Google Postmaster data, and deliverability monitoring. Many teams run both together rather than choosing one.
Key takeaways
- GMass pricing starts at $29.95/mo for the Standard plan and rises to $175/mo for the 5-user Teams plan.
- Warmy uses custom, contact-sales pricing across its B2B sender, B2C sender, and Custom plan tiers.
- GMass lists 10 features on its own page compared with 8 features listed by Warmy.
- GMass integrates with 4 tools (Gmail, Google Sheets, Zapier, Google Workspace) while Warmy integrates with 6 (Google Workspace, Microsoft 365, Gmail, Yahoo, Outlook, Google Postmaster).
- Gmail and Google Workspace are the only integrations shared by both platforms.
Reviewed and updated September 2, 2026
GMass vs Warmy: Cold Email Platform vs Email Warmup Tool Comparison
GMass (cold email platform) and Warmy (email warmup tool) sit next to each other in many outbound stacks. They are not substitutes for each other on every job, so this comparison covers pricing, features, and integrations for each and points out where the two meet.
The Quick Answer
GMass is a cold email platform for cold email outreach; Warmy is an email warmup tool for email domain warming and deliverability. By each vendor's own wording, GMass lists works inside gmail and unlimited emails, contacts, and campaigns, and Warmy lists email warm-up and email seed list.
GMass publishes an entry price of $29.95/mo; Warmy uses custom pricing, so the two cannot be compared on list price.
If your priority is sending campaigns that land in the inbox and generate replies, GMass is the one built for it; for building sender reputation and improving inbox placement, that is Warmy. Many teams run one of each.
Understanding the Core Difference
GMass is Gmail-based mass email and mail merge platform with unlimited emails, campaigns, and contacts directly inside Gmail.
Warmy is Automated email deliverability tool that warms up domains and IPs with AI-driven automation and a network of business or consumer mailboxes. Adds Google Postmaster integration, seed lists, deliverability insights and email verification in the same platform.
The two platforms take different approaches to solving the same core challenge.
Pricing Comparison
Standard
B2B sender
GMass Pricing (as of September 2026)
| Plan | Price | Contacts | Emails |
|---|---|---|---|
| Standard | $29.95/mo | Unlimited | Unlimited (Gmail limits apply) |
| Premium | $39.95/mo | Unlimited | Unlimited (Gmail limits apply) |
| Professional | $59.95/mo | Unlimited | Unlimited (Gmail limits apply) |
| Teams (5 users) | $175/mo | Unlimited | Unlimited (Gmail limits apply) |
Source: GMass Pricing
Warmy Pricing (as of September 2026)
| Plan | Price | Contacts | Emails |
|---|---|---|---|
| B2B sender | Contact Sales | Reach Businesses | Volume-based pricing |
| B2C sender | Contact Sales | Reach Consumers | Volume-based pricing |
| Custom plan | Contact Sales | Custom Solution | Volume-based pricing |
Source: Warmy Pricing
Pricing Analysis
One or both platforms use custom or contact-based pricing for some tiers. Reach out to their sales teams for exact quotes based on your usage needs.
GMass offers 4 pricing tiers compared to Warmy's 3, giving you more granularity as you scale.
Features Breakdown
- Works inside Gmail
- Unlimited emails, contacts, and campaigns
- Mail merge personalization
- Free email verification
- Automated follow-up sequences
- A/B testing
- and 4 more listed below
- Email Warm-Up
- Email Seed List
- Deliverability Insights
- Google Postmaster Integration
- Email Verification
- Warmy API
- and 2 more listed below
GMass Key Features
- Works inside Gmail
- Unlimited emails, contacts, and campaigns
- Mail merge personalization
- Free email verification
- Automated follow-up sequences
- A/B testing
- Spam Solver deliverability tool
- Custom tracking links
- Inbox rotation
- API and Zapier access
Warmy Key Features
- Email Warm-Up
- Email Seed List
- Deliverability Insights
- Google Postmaster Integration
- Email Verification
- Warmy API
- Deliverability monitor
- Dedicated deliverability expert
The two lists below are a diff of each vendor's own feature list by exact wording, so a capability both tools offer can appear on either side under a different name.
Listed only by GMass
- Works inside Gmail
- Unlimited emails, contacts, and campaigns
- Mail merge personalization
- Free email verification
- Automated follow-up sequences
- A/B testing
- Spam Solver deliverability tool
- Custom tracking links
- Inbox rotation
- API and Zapier access
Listed only by Warmy
- Email Warm-Up
- Email Seed List
- Deliverability Insights
- Google Postmaster Integration
- Email Verification
- Warmy API
- Deliverability monitor
- Dedicated deliverability expert
Integration Ecosystem
GMass Integrations
GMass connects with: Gmail, Google Sheets, Zapier, Google Workspace.
Warmy Integrations
Warmy connects with: Google Workspace, Microsoft 365, Gmail, Yahoo, Outlook, Google Postmaster.
Shared Integrations
Both tools integrate with: Gmail, Google Workspace.
Integrations listed only by GMass: Google Sheets, Zapier.
Integrations listed only by Warmy: Microsoft 365, Yahoo, Outlook, Google Postmaster.
Use Case Recommendations
Best Fit for GMass
- Budget-conscious teams looking for an affordable cold email platform
- Teams that need a wide feature set (10 capabilities listed)
- Sales teams running high-volume outbound email campaigns
- Agencies managing multiple client outreach programs
Best Fit for Warmy
- Organizations with complex tech stacks needing broad integration support (6 integrations)
- Enterprise buyers who prefer custom pricing and dedicated support
- Teams launching new email domains for outreach
- Organizations recovering from deliverability issues
Feature Comparison Summary
| Feature | GMass | Warmy |
|---|---|---|
| Starting Price | $29.95/mo | Contact Sales |
| Top Tier Price | $175/mo | Contact Sales |
| Total Features Listed | 10 | 8 |
| Integrations | 4 | 6 |
| Founded | 2015 | N/A |
Getting Started Checklist
- Define your cold email outreach and email domain warming and deliverability requirements and monthly budget
- Estimate your expected email sending volume and warmup email volume to find the right tier
- List the integrations your team currently relies on
- Sign up for free trials or demos of both platforms
- Run a small test with each tool before making a commitment
- Evaluate the onboarding experience and support quality
Final Thoughts
GMass serves the cold email outreach side of an outbound stack and Warmy the email domain warming and deliverability side. GMass publishes an entry price of $29.95/mo, while Warmy uses custom pricing for its plans, so compare on features and on the quote you receive. Your decision should weigh pricing against the specific features that matter most for your workflow.
Start with a trial of each to see which platform fits your team's daily process. The best tool is the one your team actually uses consistently.
Pricing and features verified as of September 2026. Visit GMass and Warmy for current information.
Frequently asked questions.
Frequently asked questions- What is the main difference between GMass and Warmy?
- GMass is a cold email platform for sending Gmail-based outreach campaigns with mail merge, follow-ups, and A/B testing. Warmy is an email warmup tool focused on domain and IP warming, seed lists, and deliverability monitoring to improve inbox placement. They solve different parts of the outbound process rather than competing directly.
- How much does GMass cost?
- GMass has four pricing tiers: Standard at $29.95/mo, Premium at $39.95/mo, Professional at $59.95/mo, and a 5-user Teams plan at $175/mo. All plans include unlimited contacts and emails, though Gmail's own sending limits still apply.
- How much does Warmy cost?
- Warmy does not publish fixed prices. It offers three tiers, B2B sender, B2C sender, and a Custom plan, all listed as Contact Sales with volume-based pricing, so buyers need to request a quote directly from Warmy's sales team.
- Can GMass and Warmy be used together?
- Yes, the two tools are often run side by side rather than as alternatives. GMass handles sending cold email campaigns from Gmail, while Warmy warms up the sending domain and monitors deliverability, so many teams use one of each in their outbound stack.
- Which tool has more integrations, GMass or Warmy?
- Warmy lists more integrations overall, with 6 including Google Workspace, Microsoft 365, Gmail, Yahoo, Outlook, and Google Postmaster. GMass lists 4 integrations: Gmail, Google Sheets, Zapier, and Google Workspace. Gmail and Google Workspace are the only integrations both platforms share.
About the author.
Tim Carden is CMO / CTO at RevenueFlow, which builds and operates outbound revenue engines for B2B companies. Studied at McGill University.
Tim Carden · CMO / CTO
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