Start free. Upgrade when you need more.
Available in 13 languages — from $9/month
Install free from the Chrome Web Store or Microsoft Edge — upgrade anytime inside Outlook.
| OutMass Pro | GMass Standard | |
|---|---|---|
| Monthly price | $19 | $29.95 |
| Platform | Outlook Web | Gmail |
| Languages | 13 (incl. TR, DE, FR, ES, RU, AR, HI, ZH, ZH-TW, JA, PT-BR, PT-PT) | English only |
| AI Email Writer | Included (Claude) | Not available |
| Email limit | 10,000 / month | ~15,000 (Gmail limit) |
| Mail merge | ✓ | ✓ |
| A/B testing | ✓ | ✓ |
| Follow-ups | ✓ | ✓ |
| Scheduled sending | ✓ | ✓ |
You can start on Free and upgrade anytime. Cancel anytime — no long-term contract.
We accept all major credit cards via Stripe. Subscriptions are billed monthly.
Yes — cancel from your account settings at any time. You keep access until the end of your billing period.
Yes — we offer a 30-day money-back guarantee. See our refund policy.
Your emails are sent directly through Microsoft Graph API using your own Outlook account — we never proxy or relay them through our own mail servers, and we never read your inbox. To power scheduled sending, follow-ups, A/B tests and saved templates, we do store your campaign's subject and body text on our backend; it's deleted when you delete the campaign or your account. See the Privacy Policy for details.
Yes — Microsoft 365 work and school accounts are fully supported, and most can connect right away. Only if your organization specifically restricts third-party apps will an IT administrator need to approve OutMass first (a standard Microsoft security setting). In that case you can ask your admin to approve OutMass, email support@getoutmass.com and we'll help, or sign in with a personal Outlook.com account instead — personal accounts work right away.
The extension interface comes in 13 languages: English, Turkish, German, French, Spanish, Russian, Arabic (right-to-left), Hindi, Simplified Chinese, Traditional Chinese, Japanese, Português (Brasil) and Português (Portugal). Each is a separate translation — Traditional Chinese is written in Taiwan vocabulary rather than converted from Simplified, and the two Portuguese versions are written independently. The AI Email Writer drafts in 12 of them and your recipients' unsubscribe pages are served in 12, the difference in both cases being that Portuguese is offered once rather than twice. Missing yours? Email support@getoutmass.com — we add requested languages quickly.
Sending pauses until next month, or you can upgrade your plan anytime.
OutMass sends emails through your own Microsoft Outlook account via the Graph API. Microsoft enforces its own sending limits on top of our plan quotas:
Our plan quotas (Free: 250, Starter: 2,500, Pro: 10,000 per month) apply in addition to these limits — whichever is stricter takes effect. We recommend spacing large campaigns over multiple days to avoid Microsoft rate limits and maintain sender reputation.
Microsoft may update these limits without notice. OutMass cannot override or guarantee delivery against Microsoft's platform limits.