Resend
performance benchmarks
Browse Resend's observed email API response time, error rates, and incident history over the last 90 days.
Live performance metrics
Real-world performance data from messages sent through Knock
| Message volume | Growth | Status page updates (30d) | Status page updates (90d) |
|---|---|---|---|
10M–25M | 1st of 10 → | 9 | 20 |
From April 17th to July 16th, Knock routed 10M–25M messages through Resend. For adoption, Resend ranks 1st of 10 providers based on new channel connections, with adoption holding steady over the period. Resend reported 20 status page updates over the last 90 days, 9 of which were in the last 30 days.
Response time
Response time measures how long Resend takes to accept an API request from Knock, including connection overhead and any automatic retries. Lower values mean faster message hand-off.
| Median (p50) | p90 | p95 | p99 |
|---|---|---|---|
98ms | 166ms | 199ms | 435ms |
From April 17th to July 16th, Resend averaged a daily median response time (p50) of 98ms across all days in the range, meaning half of all requests on a typical day complete in under 98ms. The 99th percentile averaged 435ms, with a peak daily p99 of 10906ms. This peak coincided with a major incident reported on Resend's status page (Degraded perfomance in Metrics). This is slightly higher than some providers, which may reflect additional processing Resend performs on message acceptance.
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.
| Avg. daily error rate | Highest daily rate | Peak error date | Zero-error days | Days above 0.01% |
|---|---|---|---|---|
0.01% | 0.57% | Jul 1 | 85 | 4 |
From April 17th to July 16th, Resend averaged a 0.01% daily error rate for 5xx responses and timeouts, with the highest single-day error rate reaching 0.57%. This is one of the lowest error rates among providers on Knock, indicating strong reliability and consistent uptime. Knock automatically retries failed requests, so transient provider errors rarely affect end-user delivery.
About these metrics: Data represents messages sent through Knock to Resend during the specified period. Response time measures time from Knock to provider acceptance. Error rate includes only provider 5xx responses and timeouts.
Recent Resend incidents
Recent status page incidents for Resend
Started Jul 16, 2026 — Resolved Jul 16, 2026
Status: Resolved We have resolved the underlying issue and service has been resumed. Affected components Automations (Operational) Single Email (Operational) Dashboard (Operational) Email Events (Operational) Broadcast Emails (Operational) General API (Operational) Webhooks (Operational) Website (Operational) SMTP (Operational) Batch Emails (Operational)
Started Jul 16, 2026 — Resolved Jul 16, 2026
Status: Resolved We have resolved the underlying issue and service has been resumed. Affected components Webhooks (Operational)
Started Jul 12, 2026 — Resolved Jul 12, 2026
Status: Resolved We have resolved the underlying issue and service has been resumed. Affected components Automations (Operational)
Started Jul 10, 2026 — Resolved Jul 10, 2026
Status: Resolved We have resolved the underlying issue and service has been resumed. Affected components Dashboard (Operational) SMTP (Operational) Broadcast Emails (Operational) Batch Emails (Operational) General API (Operational) Single Email (Operational)
Started Jul 3, 2026 — Resolved Jul 3, 2026
Status: Resolved We have resolved the underlying issue and services have been recovered. Affected components SMTP (Operational) Broadcast Emails (Operational) Batch Emails (Operational) Single Email (Operational)
Compare Resend with other providers
About Resend
Resend is a modern email API built for developers, with React Email support and a focus on simplicity.
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
Frequently asked questions
What is Resend?
Resend is an email service provider commonly used for developer-centric transactional email, react-based email templates, startup and early-stage email delivery. Resend is a modern email API built for developers, with React Email support and a focus on simplicity.
How much does Resend cost?
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. Resend offers a free tier with up to 3,000 emails, with a hard sending limit on that plan.
How fast is Resend?
Based on real-world data from messages sent through Knock, Resend accepts API requests with a median response time of 98ms (p50) and 435ms at the 99th percentile.
How reliable is Resend?
From April 17th to July 16th, Resend showed an error rate of 0.01% for 5xx responses and timeouts across 10M–25M messages sent through Knock. Knock automatically retries failed requests, so transient provider errors rarely affect end-user delivery.
What are the pros and cons of Resend?
Key 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, newer and less battle-tested compared to incumbents like mailgun or sendgrid and fewer enterprise features than established providers.
Does Resend work with Knock?
Yes. Knock has a native Resend integration that enables you to send email notifications through Resend as part of a cross-channel workflow. You can combine Resend with other channels like in-app feeds, push, SMS, and Slack from a single API call.
Use Resend with Knock
Knock enables you to integrate Resend alongside other notification channels, manage templates, and orchestrate cross-channel workflows from a single platform.