Compare Mailjet against Resend API performance
Compare real-time performance, reliability, and uptime benchmarks for Mailjet and Resend, powered by proprietary data from billions of messages sent through Knock.
Live performance comparison
Real-world performance data from messages sent through Knock.
| Provider | Message volume | Growth | Status page updates (30d) | Status page updates (90d) |
|---|---|---|---|---|
 | <1M | 6th of 10 → | 0 | 2 |
 | 10M–25M | 1st of 10 → | 2 | 2 |
From August 13th to November 11th, Knock routed <1M messages through Mailjet and 10M–25M through Resend. Mailjet reported 2 status page updates over the last 90 days, while Resend reported 2.
Response time
Response time measures how long each provider takes to accept an API request from Knock, including connection overhead and any automatic retries. Lower values mean faster message hand-off.
The chart above shows each provider's daily median response time (p50) from August 13th to November 11th. The top-line number is an average of these daily values: Mailjet averaged 406ms compared to 70ms for Resend. Mailjet's highest daily p50 was 446ms; Resend's was 96ms. Resend is 336ms faster at the median, which can add up at high volumes.
The 90th percentile (p90) captures the slowest 10% of requests, revealing how each provider handles moderate stress. Averaged across all days, Mailjet has a p90 of 594ms compared to 102ms for Resend. The highest daily p90 was 1020ms for Mailjet and 146ms for Resend. Resend handles these slower requests 492ms faster, suggesting more consistent performance across the board.
The 99th percentile (p99) represents the long tail — the slowest 1% of requests. Averaged across all days, Mailjet reached 746ms at p99 while Resend reached 304ms. The highest daily p99 was 2503ms for Mailjet and 1793ms for Resend, indicating the worst-case response time during spikes or provider-side congestion. Resend shows a tighter tail, which may matter for time-sensitive notifications like one-time passwords or real-time alerts where even rare delays can impact user experience.
Error rate
Error rate tracks the ratio of 5xx responses and timeouts to total requests. Knock automatically retries failed requests, so transient provider errors rarely affect end-user delivery.
| Provider | Avg. daily error rate | Highest daily rate | Peak error date | Zero-error days | Days above 0.01% |
|---|---|---|---|---|---|
| 0.00% | 0.00% | Aug 13 | 91 | 0 |
| 0.00% | 0.09% | Oct 1 | 89 | 2 |
Averaged across the date range, Mailjet shows a 0.00% daily error rate compared to 0.00% for Resend. The highest single-day error rate was 0.00% for Mailjet and 0.09% for Resend. Both providers show similar reliability levels, with error rates well within acceptable thresholds. Knock automatically retries failed requests to both providers, minimizing the impact of transient errors on end-user delivery.
About these metrics: Data represents messages sent through Knock during the specified period. Response time measures time from Knock to provider acceptance. Error rate includes only provider 5xx responses and timeouts.
Recent Mailjet incidents
Recent status page incidents for Mailjet
Started Sep 23, 2026 — Resolved Sep 23, 2026
Sep 23, 05:00 UTC Completed - The scheduled maintenance has been completed. Sep 23, 04:00 UTC In progress - Scheduled maintenance is currently in progress. We will provide updates as necessary. Sep 15, 08:10 UTC Scheduled - We’ll be performing scheduled infrastructure maintenance on Wednesday, September 23, starting at 4:00 AM UTC. The estimated impact duration is 30 minutes. During this window, you won't be able to log in or send new messages via SMTP or API. Don't worry, any emails alr
Started Sep 4, 2026 — Resolved Sep 4, 2026
Sep 4, 12:55 UTC Resolved - This incident has been resolved. Sep 4, 12:23 UTC Monitoring - Starting around 08:00 UTC, Microsoft began experiencing an incident causing an increased volume of deferred emails across all M365 regions. The affected responses are returning "451 4.7.500 Server busy". Our teams are actively monitoring the situation. Sending to other email providers is not affected.
Recent Resend incidents
Recent status page incidents for Resend
Started Oct 26, 2026 — Resolved Oct 26, 2026
Status: Resolved Email status updates are processing normally again. All delayed updates have been delivered, and no data was lost. Affected components Email Events (Operational)
Started Oct 23, 2026 — Resolved Oct 23, 2026
Status: Resolved We have resolved the underlying issue and service has been resumed. Affected components Single Email (Operational) Broadcast Emails (Operational) Batch Emails (Operational) Scheduled Emails (Operational)
Pros and cons
Compare the strengths and tradeoffs between Mailjet and Resend.
Mailjet
Pros
- Hybrid support for both marketers and developers in a single platform
- Unique real-time collaboration features for team-based template editing
- EU-only data processing for companies with strict data residency requirements
- Powers email delivery for over 130,000 companies including Microsoft and DHL
Cons
- Activated automation workflows cannot be edited, requiring new workflows for any changes
- Some analytics and deliverability tools are locked behind higher pricing plans
- Deliverability can lag behind specialists like Postmark
Resend
Pros
- Beautiful documentation with attention to detail and great developer experience
- Created and maintain React Email, the go-to framework for building email templates in React
- Minimalist, developer-optimized platform that avoids bloat with a focused UI
- Transparent observability with real-time visibility into sends, failures, and engagement
Cons
- Newer and less battle-tested compared to incumbents like Mailgun or SendGrid
- Fewer enterprise features than established providers
- Limited marketing email capabilities
Pricing comparison
Compare Mailjet and Resend as your email volume grows.
Frequently asked questions
Mailjet is a collaborative email platform with real-time editing and combined transactional and marketing capabilities. Resend is a modern email API built for developers, with React Email support and a focus on simplicity. Mailjet is best suited for team collaboration + marketing, while Resend is geared toward developer-first, react teams.
Free tier includes 200 emails per day (6,000/month). Paid plans start at $17/month for 15,000 emails with no daily limit. Premium plans start at $105/month for 100,000 emails. Free tier includes 3,000 emails per month and 100 emails per day. Paid plans start at $20/month for 50,000 emails with overages at $0.90/1K on Pro, scaling down to $0.46/1K on Scale 2.5M. The best value depends on your sending volume. Use the pricing calculator above to compare costs at your expected volume.
Based on real-world data from Knock, Mailjet has a median API response time (p50) of 406ms compared to 70ms for Resend.
From August 13th to November 11th, Mailjet showed an error rate of 0.00% while Resend showed 0.00%. Both rates are within acceptable thresholds for production email delivery, and Knock automatically retries failed requests to minimize the impact of transient errors.
On the Knock platform, Mailjet handled <1M messages from August 13th to November 11th compared to 10M–25M for Resend. Mailjet volume has remained stable, while Resend volume has remained stable.
Yes. Knock enables you to integrate multiple email providers into a single notification workflow. You can use Mailjet and Resend side by side, route traffic between them, or migrate from one to the other without changing your application code.
Mailjet strengths include hybrid support for both marketers and developers in a single platform and unique real-time collaboration features for team-based template editing. Resend strengths include beautiful documentation with attention to detail and great developer experience and created and maintain react email, the go-to framework for building email templates in react. On the other hand, Mailjet drawbacks include activated automation workflows cannot be edited, requiring new workflows for any changes, while Resend drawbacks include newer and less battle-tested compared to incumbents like mailgun or sendgrid.