GMass: Powerful mail merge for Gmail

Tracking since Apr 1, 2026.

Changelog

• Jun 4, 2026
  description

  The easiest way to transform Gmail into a cold outreach, email marketing, and mail merge platform.
  
  ** Join the almost 400,000 others who’ve given us an average of 4.8 out of 5 stars **
  
  No credit card required + send 50 emails per day free during your free trial!
  
  -----------------------------------------
  Key features
  -----------------------------------------
  * Send cold email and email marketing messages to thousands of addresses
  
  * Unlimited contacts, campaigns, AND emails
  
  * Mail merge personalization with data from Google Sheets
  
  * Personalize each mass email (even send personalized images and attachments)
  
  * With GMass MultiSend's inbox rotation feature, you can distribute your campaign across multiple accounts! 
  
  * Hit the inbox, not the spam folder. 99% of GMass users report the best deliverability they’ve ever had.
  
  * Spam Solver - test messages before you send to find spam rates, then use suggested tweaks to improve
  
  * Send auto follow-ups based on opens, clicks, and replies. NEW - Send any stage of follow-ups on demand.
  
  * ChatGPT campaign creation — generate an entire email campaign, follow-ups, and GMass settings by typing in a prompt
  
  * Automatically skip sending emails and automations on holidays, and choose custom days of the week to send/not send a campaign
  
  * Send triggered emails that go out automatically when a recipient opens or clicks — reach your prospects when you know they're in their inbox
  
  * Automate your outreach by automatically sending to new contacts in your Sheet using GMass's recurring campaigns
  
  * Connect your CRM or other apps using the GMass API or Zapier
  
  * Track opens, clicks, and replies — with instant reply and bounce detection. No more delays; see replies and bounces in your report in a matter of seconds.
  
  * Free email verification — verify email addresses before you send your campaigns
  
  * Set DKIM through GMass for authenticated sending with a SMTP server.
  
  * Help with the new Google/Yahoo bulk sender requirements is here - https://www.gmass.co/blog/gmail-bulk-sender-guidelines/. We've also created a one-of-a-kind system to help users with free Gmail addresses sending campaigns via a SMTP server pass DMARC - https://www.gmass.co/blog/gmail-smtp-dmarc/
  
  * Emails can be sent as replies to the last conversation you had with each recipient
  
  * Unsubscribe and bounce management to automatically process unsubs/bounces, suppress future messages to those addresses, and more.
  
  * Hundreds of other features: Schedule emails, throttle sending speed, custom tracking links with SSL, A/B testing, spintax for varying up your copy, quick email polls with custom landing pages, add a countdown timer to emails, drip campaigns, HTML editing, use Gmail's built-in layouts for email marketing, 1-click replies, reusable templates, one-click social media sharing of campaign results, and so much more
  
  -----------------------------------------
  Keep up with GMass
  -----------------------------------------
  Website: https://www.gmass.co
  
  What makes GMass different/better? https://www.gmass.co/blog/what-makes-gmass-better/
  
  Quickstart guide: https://www.gmass.co/quickstart-guide
  
  Blog: https://www.gmass.co/blog
  
  Twitter: https://twitter.com/GMassForGmail and https://twitter.com/PartTimeSnob
  
  YouTube: https://www.youtube.com/gmass/
  
  Support: https://gmass.co/g/support
  
  Latest updates: https://www.gmass.co/updates
  
  -----------------------------------------
  How does GMass compare to other Gmail extensions?
  -----------------------------------------
  Mixmax: cool extension, but you have to use its external web portal to send campaigns. With GMass, the magic happens inside Gmail, using just the red GMass button.
  
  Yesware: similar to Mixmax, you can't send campaigns inside Gmail. You have to use their web interface.
  
  Plus, both Mixmax and Yesware are more expensive than GMass.
  
  Mailtrack and Snov.io: Lets you track individual emails, but with GMass, you can eliminate Mailtrack and Snov.io because GMass can track both individual emails and campaign emails. Use the GMass button on both one-on-one emails and campaigns.
  
  Copper: Good CRM system, but not meant for sending email campaigns. Same for
  Gmelius and Streak CRM.
  
  Lastly, GMass works seamlessly with Grammarly to ensure your campaigns contain perfect prose and are error-free.

  The easiest way to transform Gmail into a cold outreach, email marketing, and mail merge platform.
  
  ** Join the 400,000+ others who’ve given us an average of 4.8 out of 5 stars **
  
  No credit card required + try all features during your free trial!
  
  -----------------------------------------
  Key features
  -----------------------------------------
  * Send cold email, email marketing messages, and mail merges to thousands of addresses without ever leaving Gmail
  
  * Unlimited contacts, campaigns, AND emails
  
  * Also: Unlimited email verification and unlimited spam solving (find out and fix issues before you send)
  
  * Mail merge personalization with data from Google Sheets
  
  * Personalize each mass email (even send personalized images and attachments)
  
  * Break Gmail's limits (and we'll help you do it with our in-house sending servers for both opt-in and cold outreach campaigns)
  
  * With GMass MultiSend's inbox rotation feature, you can distribute your campaign across multiple accounts
  
  * Hit the inbox, not the spam folder. 99% of GMass users report the best deliverability they’ve ever had
  
  * Spam Solver - test messages before you send to find spam rates, then use suggested tweaks to improve
  
  * Send auto follow-ups based on opens, clicks, and replies.
  
  * ChatGPT campaign creation generates an entire email campaign, creates a follow-up sequence, and handles your GMass settings
  
  * AI template builder creates beautiful HTML email layouts right in Gmail
  
  * Automatically skip sending emails and automations on holidays, and choose custom days of the week to send/not send a campaign
  
  * Send triggered emails that go out automatically when a recipient opens or clicks — reach your prospects when you know they're in their inbox
  
  * Automate your outreach by automatically sending to new contacts in your Sheet
  
  * Connect your CRM or other apps using the GMass API or Zapier
  
  * Track opens, clicks, and replies. With instant reply and bounce detection and some of the most accurate open rates you'll find anywhere
  
  * Free email verification verify email addresses before you send your campaigns
  
  * Help with the Google/Yahoo bulk sender requirements is here. We've also created a one-of-a-kind system to help users with free Gmail addresses sending campaigns via a SMTP server pass DMARC - https://www.gmass.co/blog/gmail-smtp-dmarc/
  
  * Emails can be sent as replies to the last conversation you had with each recipient
  
  * Unsubscribe and bounce management to automatically process unsubs/bounces, suppress future messages to those addresses, and more.
  
  * Hundreds of other features: Schedule emails, throttle sending speed, custom tracking links with SSL, A/B testing, spintax for varying up your copy (and AI's SpinMax to vary up every message), quick email polls with custom landing pages, add a countdown timer to emails, drip campaigns, HTML editing, 1-click replies, reusable templates, template sharing for teams, and so much more
  
  * And yet, even with all these features... sending an email campaign with GMass is just like using regular Gmail
  
  -----------------------------------------
  Keep up with GMass
  -----------------------------------------
  Website: https://www.gmass.co
  
  What makes GMass different/better? https://www.gmass.co/blog/what-makes-gmass-better/
  
  Quickstart guide: https://www.gmass.co/quickstart-guide
  
  Blog: https://www.gmass.co/blog
  
  YouTube: https://www.youtube.com/gmass/
  
  Support: https://gmass.co/g/support
  
  Latest updates: https://www.gmass.co/updates
  
  -----------------------------------------
  How does GMass compare to other Gmail extensions?
  -----------------------------------------
  Mixmax: cool extension, but you have to use its external web portal to send campaigns. (Also, Mixmax is much more of a sales team management platform than an email sending platform.) With GMass, the magic happens inside Gmail, using just the red GMass button.
  
  Yesware: similar to Mixmax, you can't send campaigns inside Gmail. You have to use their web interface.
  
  Plus, both Mixmax and Yesware are more expensive than GMass.
  
  Mailtrack and Snov.io: Lets you track individual emails, but with GMass, you can eliminate Mailtrack and Snov.io because GMass can track both individual emails and campaign emails. (Use the GMass button on both one-on-one emails and campaigns.)
  
  Copper: Good CRM system, but not meant for sending email campaigns. Same for Gmelius and Streak CRM.
  
  Lastly, GMass works seamlessly with Grammarly to ensure your campaigns contain perfect prose and are error-free.

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