Email APIs · side by side
Customer.io vs Mailjet
Compare Customer.io, Mailjet by sending volume, delivery webhooks, inbound email, domain limits and retention.
Email APIs pricing calculator
These providers bill in different units. Each estimate uses its own workload; there is no same-volume price winner.
Customer.io
25K
Mailjet
0
Customer.io
$100 / mo
Essentials · 25K profiles
Mailjet
$0 / mo
Free · 0 emails
Listed USD plan fees and tracked usage only. Unlisted compute, transfer, extras, taxes and contract terms are excluded. Custom or unsupported plan usage is not estimated.
Email APIs overview & pricing
| Email APIs | Customer.io | Mailjet |
|---|---|---|
| Provider | Customer.io | Sinch |
| Billing unit | profiles | emails |
| Plan at selected usage | Essentials | Free |
| Monthly estimate | $100/mo | $0/mo |
| Workload | 25K profiles | 0 emails |
| Free access | Trial | Free plan includes 6,000 emails per month capped at 200 emails per day, with up to 1,000 contacts, API/SMTP relay access |
| Published plans | Essentials, Premium, Enterprise | Free, Starter, Essential, Premium, Custom |
| Prices checked | 2026-10-08 | 2026-10-08 |
Provider
- Customer.io
- Customer.io
- Mailjet
- Sinch
Billing unit
- Customer.io
- profiles
- Mailjet
- emails
Plan at selected usage
- Customer.io
- Essentials
- Mailjet
- Free
Monthly estimate
- Customer.io
- $100/mo
- Mailjet
- $0/mo
Workload
- Customer.io
- 25K profiles
- Mailjet
- 0 emails
Free access
- Customer.io
- Trial
- Mailjet
- Free plan includes 6,000 emails per month capped at 200 emails per day, with up to 1,000 contacts, API/SMTP relay access
Published plans
- Customer.io
- Essentials, Premium, Enterprise
- Mailjet
- Free, Starter, Essential, Premium, Custom
Prices checked
- Customer.io
- 2026-10-08
- Mailjet
- 2026-10-08
Email APIs monthly cost
Customer.io: $100Mailjet: $0
Different workloads, separate estimates
Separate transactional delivery from campaigns, outreach and agent inboxes. Compare monthly sends and daily caps; contacts, seats and inboxes are not sending allowances. Budget separately for dedicated IPs, validation and attachments.
Email APIs feature comparison
| Email APIs | Customer.io | Mailjet |
|---|---|---|
| Dedicated IP | Not listed | |
| AI Agent (beta): Session limits | Standard | Not listed |
| AI Agent (beta): Persistent Memory | Not listed | |
| AI Agent (beta): Core Execution Skills | Not listed | |
| AI Agent (beta): Custom Execution Skills | 3 | Not listed |
| AI Agent (beta): Routines: # of tasks | 1 | Not listed |
| AI Agent (beta): Routines: frequency | Weekly | Not listed |
| Monthly email sends | 1M | Not listed |
| Transactional emails | Not listed | |
| Monthly push and in-app | Unlimited | Not listed |
| Mobile SDKs | Not listed | |
| Monthly SMS sends | Custom | Not listed |
| WhatsApp (Native) | Not listed | |
| LINE | Not listed | |
| Webhook (send & receive) | Unlimited | Not listed |
| Anonymous messages | — Not included | Not listed |
| LLM actions | Not listed | |
| Visual workflow builder | Not listed | |
| Cross-channel campaign automation | Not listed | |
| Send-time optimization | Not listed | |
| In-app message suggestions | Not listed | |
| API-triggered broadcasts | Not listed | |
| Scalable Personalization | Not listed | |
| Custom SMTP | Not listed | |
| Profiles (people + objects) | 5,000 | Not listed |
| People attributes | Unlimited | Not listed |
| Custom objects | Not listed | |
| Object types | 2 | Not listed |
| Segments | Not listed | |
| AI-powered segment builder | Not listed | |
| Suggested segments | Not listed | |
| Nested data | Not listed | |
| Ad audience sync | Not listed | |
| Custom collections | — Not included | Not listed |
| Drag-and-drop visual editor | Not listed | |
| Code editor | Not listed | |
| AI-generated global styles | Not listed | |
| AI translator for messages | Not listed | |
| Email content analysis | Not listed | |
| Reusable components | Not listed | |
| Saved templates & version control | Not listed | |
| Inbox previews | 25 | Not listed |
| Monthly API calls | Unlimited | Not listed |
| Integrations | Basic | |
| MCP server | Not listed | |
| Data index | Not listed | |
| Connected forms | Not listed | |
| Privacy management | Not listed | |
| Reverse ETL | Not listed | |
| Data warehouse destinations | — Not included | Not listed |
| Data replay | — Not included | Not listed |
| Dashboards | Not listed | |
| Campaign reporting | Not listed | |
| Workspace performance dashboard | Not listed | |
| Survey analysis | Not listed | |
| Data export | Not listed | |
| A/B & multivariate testing | Not listed | |
| Conversion tracking | Not listed | |
| Universal search | Not listed | |
| SSO & 2-factor authentication | Not listed | |
| US / EU data centers | Not listed | |
| SOC Tier II Compliance | Not listed | |
| Standard role-based permissions | Not listed | |
| Custom role-based permissions | — Not included | Not listed |
| Managed deliverability | — Not included | Not listed |
| HIPAA Compliance | — Not included | Not listed |
| Audit logging & data governance | — Not included | Not listed |
| Dedicated hardware | — Not included | Not listed |
| Documentation | Not listed | |
| Community support | Not listed | |
| Email support | Not listed | |
| Chat support | — Not included | Not listed |
| Onboarding support | — Not included | Not listed |
| Dedicated Customer Success Manager | — Not included | Not listed |
| Migration support | — Not included | Not listed |
| Dedicated Technical Implementation Specialist | — Not included | Not listed |
| Shared Slack channel | — Not included | Not listed |
| 2-hour first outreach response time | — Not included | Not listed |
| User seats | Unlimited | Not listed |
| Workspaces | 2 | Not listed |
| Additional people & object profiles | $0.009 | Not listed |
| Advanced Email Editor | Not listed | |
| Email Templates | Not listed | |
| Unlimited Contacts | Not listed | |
| GDPR-Compliant Subscription Forms | Not listed | |
| MJML | Not listed | |
| No Mailjet Logo | Not listed | |
| Saved, Locked and Linked Sections | Not listed | |
| Landing Pages | Not listed | |
| AI Assisted content creation | Not listed | |
| Personalization | Not listed | |
| Templating Language | Not listed | |
| Segmentation | Not listed | |
| Brand Kit | Not listed | |
| Dynamic Content | Not listed | |
| Automations | Not listed | |
| Custom Unsubscribe Page | Not listed | |
| Preference Center | Not listed | |
| Email Tracking Consent | Not listed | |
| Anonymous Tracking | Not listed | |
| Basic Statistics | Not listed | |
| Webhooks (event API) | Not listed | |
| Advanced Statistics | Not listed | |
| Validations | Not listed | |
| Campaign Comparison | Not listed | |
| A/B Testing | Not listed | |
| Email Previews | Not listed | |
| Monthly Deliverability Reports and Recommendations | Not listed | |
| Send API | Not listed | |
| SMTP Relay | Not listed | |
| Multi-user Access | Not listed | |
| Multi-user Collaboration | Not listed | |
| Advanced permissions | Not listed | |
| Predefined roles | Not listed | |
| Activity Logs | Not listed | |
| Subaccounts | Not listed | |
| Online Customer Support | Not listed | First Month Only |
| Priority Support | Not listed | |
| Phone and Chat Support | Not listed | |
| Dedicated Technical Account Manager | Not listed | |
| Deliverability Services | Not listed | |
| Comprehensive onboarding | Not listed | |
| API Expert | Not listed | |
| Custom deliverability strategy | Not listed | |
| Reputation monitoring | Not listed | |
| Service Level Agreement | Not listed | |
| Deliverability and platform training for your team | Not listed |
Dedicated IP
- Customer.io
- Not listed
- Mailjet
AI Agent (beta): Session limits
- Customer.io
- Standard
- Mailjet
- Not listed
AI Agent (beta): Persistent Memory
- Customer.io
- Mailjet
- Not listed
AI Agent (beta): Core Execution Skills
- Customer.io
- Mailjet
- Not listed
AI Agent (beta): Custom Execution Skills
- Customer.io
- 3
- Mailjet
- Not listed
AI Agent (beta): Routines: # of tasks
- Customer.io
- 1
- Mailjet
- Not listed
AI Agent (beta): Routines: frequency
- Customer.io
- Weekly
- Mailjet
- Not listed
Monthly email sends
- Customer.io
- 1M
- Mailjet
- Not listed
Transactional emails
- Customer.io
- Mailjet
- Not listed
Monthly push and in-app
- Customer.io
- Unlimited
- Mailjet
- Not listed
Mobile SDKs
- Customer.io
- Mailjet
- Not listed
Monthly SMS sends
- Customer.io
- Custom
- Mailjet
- Not listed
WhatsApp (Native)
- Customer.io
- Mailjet
- Not listed
LINE
- Customer.io
- Mailjet
- Not listed
Webhook (send & receive)
- Customer.io
- Unlimited
- Mailjet
- Not listed
Anonymous messages
- Customer.io
- — Not included
- Mailjet
- Not listed
LLM actions
- Customer.io
- Mailjet
- Not listed
Visual workflow builder
- Customer.io
- Mailjet
- Not listed
Cross-channel campaign automation
- Customer.io
- Mailjet
- Not listed
Send-time optimization
- Customer.io
- Mailjet
- Not listed
In-app message suggestions
- Customer.io
- Mailjet
- Not listed
API-triggered broadcasts
- Customer.io
- Mailjet
- Not listed
Scalable Personalization
- Customer.io
- Mailjet
- Not listed
Custom SMTP
- Customer.io
- Mailjet
- Not listed
Profiles (people + objects)
- Customer.io
- 5,000
- Mailjet
- Not listed
People attributes
- Customer.io
- Unlimited
- Mailjet
- Not listed
Custom objects
- Customer.io
- Mailjet
- Not listed
Object types
- Customer.io
- 2
- Mailjet
- Not listed
Segments
- Customer.io
- Mailjet
- Not listed
AI-powered segment builder
- Customer.io
- Mailjet
- Not listed
Suggested segments
- Customer.io
- Mailjet
- Not listed
Nested data
- Customer.io
- Mailjet
- Not listed
Ad audience sync
- Customer.io
- Mailjet
- Not listed
Custom collections
- Customer.io
- — Not included
- Mailjet
- Not listed
Drag-and-drop visual editor
- Customer.io
- Mailjet
- Not listed
Code editor
- Customer.io
- Mailjet
- Not listed
AI-generated global styles
- Customer.io
- Mailjet
- Not listed
AI translator for messages
- Customer.io
- Mailjet
- Not listed
Email content analysis
- Customer.io
- Mailjet
- Not listed
Reusable components
- Customer.io
- Mailjet
- Not listed
Saved templates & version control
- Customer.io
- Mailjet
- Not listed
Inbox previews
- Customer.io
- 25
- Mailjet
- Not listed
Monthly API calls
- Customer.io
- Unlimited
- Mailjet
- Not listed
Integrations
- Customer.io
- Basic
- Mailjet
MCP server
- Customer.io
- Mailjet
- Not listed
Data index
- Customer.io
- Mailjet
- Not listed
Connected forms
- Customer.io
- Mailjet
- Not listed
Privacy management
- Customer.io
- Mailjet
- Not listed
Reverse ETL
- Customer.io
- Mailjet
- Not listed
Data warehouse destinations
- Customer.io
- — Not included
- Mailjet
- Not listed
Data replay
- Customer.io
- — Not included
- Mailjet
- Not listed
Dashboards
- Customer.io
- Mailjet
- Not listed
Campaign reporting
- Customer.io
- Mailjet
- Not listed
Workspace performance dashboard
- Customer.io
- Mailjet
- Not listed
Survey analysis
- Customer.io
- Mailjet
- Not listed
Data export
- Customer.io
- Mailjet
- Not listed
A/B & multivariate testing
- Customer.io
- Mailjet
- Not listed
Conversion tracking
- Customer.io
- Mailjet
- Not listed
Universal search
- Customer.io
- Mailjet
- Not listed
SSO & 2-factor authentication
- Customer.io
- Mailjet
- Not listed
US / EU data centers
- Customer.io
- Mailjet
- Not listed
SOC Tier II Compliance
- Customer.io
- Mailjet
- Not listed
Standard role-based permissions
- Customer.io
- Mailjet
- Not listed
Custom role-based permissions
- Customer.io
- — Not included
- Mailjet
- Not listed
Managed deliverability
- Customer.io
- — Not included
- Mailjet
- Not listed
HIPAA Compliance
- Customer.io
- — Not included
- Mailjet
- Not listed
Audit logging & data governance
- Customer.io
- — Not included
- Mailjet
- Not listed
Dedicated hardware
- Customer.io
- — Not included
- Mailjet
- Not listed
Documentation
- Customer.io
- Mailjet
- Not listed
Community support
- Customer.io
- Mailjet
- Not listed
Email support
- Customer.io
- Mailjet
- Not listed
Chat support
- Customer.io
- — Not included
- Mailjet
- Not listed
Onboarding support
- Customer.io
- — Not included
- Mailjet
- Not listed
Dedicated Customer Success Manager
- Customer.io
- — Not included
- Mailjet
- Not listed
Migration support
- Customer.io
- — Not included
- Mailjet
- Not listed
Dedicated Technical Implementation Specialist
- Customer.io
- — Not included
- Mailjet
- Not listed
Shared Slack channel
- Customer.io
- — Not included
- Mailjet
- Not listed
2-hour first outreach response time
- Customer.io
- — Not included
- Mailjet
- Not listed
User seats
- Customer.io
- Unlimited
- Mailjet
- Not listed
Workspaces
- Customer.io
- 2
- Mailjet
- Not listed
Additional people & object profiles
- Customer.io
- $0.009
- Mailjet
- Not listed
Advanced Email Editor
- Customer.io
- Not listed
- Mailjet
Email Templates
- Customer.io
- Not listed
- Mailjet
Unlimited Contacts
- Customer.io
- Not listed
- Mailjet
GDPR-Compliant Subscription Forms
- Customer.io
- Not listed
- Mailjet
MJML
- Customer.io
- Not listed
- Mailjet
No Mailjet Logo
- Customer.io
- Not listed
- Mailjet
Saved, Locked and Linked Sections
- Customer.io
- Not listed
- Mailjet
Landing Pages
- Customer.io
- Not listed
- Mailjet
AI Assisted content creation
- Customer.io
- Not listed
- Mailjet
Personalization
- Customer.io
- Not listed
- Mailjet
Templating Language
- Customer.io
- Not listed
- Mailjet
Segmentation
- Customer.io
- Not listed
- Mailjet
Brand Kit
- Customer.io
- Not listed
- Mailjet
Dynamic Content
- Customer.io
- Not listed
- Mailjet
Automations
- Customer.io
- Not listed
- Mailjet
Custom Unsubscribe Page
- Customer.io
- Not listed
- Mailjet
Preference Center
- Customer.io
- Not listed
- Mailjet
Email Tracking Consent
- Customer.io
- Not listed
- Mailjet
Anonymous Tracking
- Customer.io
- Not listed
- Mailjet
Basic Statistics
- Customer.io
- Not listed
- Mailjet
Webhooks (event API)
- Customer.io
- Not listed
- Mailjet
Advanced Statistics
- Customer.io
- Not listed
- Mailjet
Validations
- Customer.io
- Not listed
- Mailjet
Campaign Comparison
- Customer.io
- Not listed
- Mailjet
A/B Testing
- Customer.io
- Not listed
- Mailjet
Email Previews
- Customer.io
- Not listed
- Mailjet
Monthly Deliverability Reports and Recommendations
- Customer.io
- Not listed
- Mailjet
Send API
- Customer.io
- Not listed
- Mailjet
SMTP Relay
- Customer.io
- Not listed
- Mailjet
Multi-user Access
- Customer.io
- Not listed
- Mailjet
Multi-user Collaboration
- Customer.io
- Not listed
- Mailjet
Advanced permissions
- Customer.io
- Not listed
- Mailjet
Predefined roles
- Customer.io
- Not listed
- Mailjet
Activity Logs
- Customer.io
- Not listed
- Mailjet
Subaccounts
- Customer.io
- Not listed
- Mailjet
Online Customer Support
- Customer.io
- Not listed
- Mailjet
- First Month Only
Priority Support
- Customer.io
- Not listed
- Mailjet
Phone and Chat Support
- Customer.io
- Not listed
- Mailjet
Dedicated Technical Account Manager
- Customer.io
- Not listed
- Mailjet
Deliverability Services
- Customer.io
- Not listed
- Mailjet
Comprehensive onboarding
- Customer.io
- Not listed
- Mailjet
API Expert
- Customer.io
- Not listed
- Mailjet
Custom deliverability strategy
- Customer.io
- Not listed
- Mailjet
Reputation monitoring
- Customer.io
- Not listed
- Mailjet
Service Level Agreement
- Customer.io
- Not listed
- Mailjet
Deliverability and platform training for your team
- Customer.io
- Not listed
- Mailjet
Showing 15 of 127
Which email providers fit your needs?
Customer.io features & plan notes
- Behavioral messaging
- Lifecycle workflows
- Event triggers
- 5k profiles (people + objects)
- AI Agent with core execution skills
- 1 million emails per month
- 2 object types
- Visual workflow builder
- Email and community support
- Basic data integrations
Mailjet features & plan notes
- Send transactional and marketing emails via Send API v3.1 or SMTP relay
- Real-time event webhooks for opens, clicks, bounces, spam complaints, and blocks
- Responsive email builder with support for MJML open-source markup
- Contact list management, email address validations, and inbox preview testing
- 1,000 contacts
- APIs, SMTP Relay, Webhooks
- Advanced Email Editor
- Basic Statistics
- Form Builder
- Email Tracking Consent
How to compare email providers
Separate transactional delivery from campaigns, outreach and agent inboxes. Compare monthly sends and daily caps; contacts, seats and inboxes are not sending allowances. Budget separately for dedicated IPs, validation and attachments.
Browse Email APIs pricing