GMass vs Warmbox
A factual comparison of features, pricing, and capabilities
Last updated: 2/6/2026
Gmail-based mass email and mail merge platform with unlimited emails, campaigns, and contacts directly inside Gmail.
Starting at: $30/month
Pricing Comparison
Prices shown are monthly rates. Annual billing may offer discounts. Visit official websites for current pricing.
Feature Comparison
| Feature | GMass | Warmbox |
|---|---|---|
| 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 | ||
| Automated email warmup with AI-powered interactions | ||
| Customizable warmup recipes and strategies | ||
| Spam score monitoring and blacklist checks | ||
| Real-time analytics and reporting dashboard | ||
| DNS checker (SPF, DKIM, DMARC) | ||
| Multi-inbox support within a single account | ||
| Auto-reply, open, and favorite marking simulation | ||
| Team collaboration with per-plan member limits |
Available
Partial/Limited
Not Available
Integrations
GMass
GmailGoogle SheetsZapierGoogle Workspace
Warmbox
GmailGoogle WorkspaceOutlookMicrosoft 365Yahoo MailAmazon SESSMTPZoho Mail
Information on this page is gathered from official sources and may change. Pricing and features were last verified on 2/6/2026. Please visit the official websites for the most current information.