Amazon SES vs Resend
Compare Amazon SES and Resend based on observed API performance, features, and pricing
Live performance comparison
Real-world performance data from messages sent through Knock
| Provider | Message volume | Growth | Status page updates (30d) | Status page updates (90d) |
|---|---|---|---|---|
| 25M–100M | 3rd of 10 ↓ | 0 | 0 |
| 10M–25M | 1st of 10 → | 7 | 26 |
From February 10th to May 11th, Knock routed 25M–100M messages through Amazon SES and 10M–25M through Resend. Amazon SES reported 0 status page updates over the last 90 days, while Resend reported 26.
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.
| Provider | Median (p50) | p90 | p95 | p99 |
|---|---|---|---|---|
| 153ms | 204ms | 231ms | 406ms |
| 81ms | 133ms | 158ms | 353ms |
The chart above shows each provider's daily median response time (p50) from February 10th to May 11th. The top-line number is an average of these daily values: Amazon SES averaged 153ms compared to 81ms for Resend. Amazon SES's highest daily p50 was 172ms; Resend's was 118ms. Resend is 72ms 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, Amazon SES has a p90 of 204ms compared to 133ms for Resend. The highest daily p90 was 241ms for Amazon SES and 171ms for Resend. Resend handles these slower requests 71ms 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, Amazon SES reached 406ms at p99 while Resend reached 353ms. The highest daily p99 was 488ms for Amazon SES and 10020ms 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% | 0.01% | Mar 31 | 90 | 0 |
| 0.07% | 2.45% | Feb 15 | 82 | 5 |
Averaged across the date range, Amazon SES shows a 0.00% daily error rate compared to 0.07% for Resend. The highest single-day error rate was 0.01% for Amazon SES and 2.45% for Resend. Amazon SES demonstrates a lower error rate, indicating slightly more consistent availability during this period. 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 Amazon SES incidents
Recent status page incidents for Amazon SES
No incidents reported in the last 90 days
Recent Resend incidents
Recent status page incidents for Resend
Started May 6, 2026 — Resolved May 6, 2026
Status: Resolved This incident is resolved. All failed provisioning requests have been reprocessed, and custom tracking domain creation is operating normally.
Started May 5, 2026 — Resolved May 5, 2026
Status: Complete We've successfully completed our maintenance, and the logs page is now behaving normally. Affected components Dashboard (Operational)
Started Apr 28, 2026 — Resolved Apr 28, 2026
Status: Resolved This incident is resolved. Webhook deliveries and metrics page updates have been stable since our fix was deployed. Sending and receiving were unaffected throughout. Thanks for your patience. Affected components Email Events (Operational)
Started Apr 27, 2026 — Resolved Apr 27, 2026
Status: Resolved This incident is resolved. Email events are updating in real time and have been stable since our fix was deployed. Sending and delivery were unaffected throughout. Thank you for your patience. Affected components Email Events (Operational)
Started Apr 24, 2026 — Resolved Apr 24, 2026
Status: Resolved The processing backlog is fully cleared. All systems are operational. Affected components Email Events (Operational)
Pros and cons
Amazon SES
Resend
Pros
- Delivers billions of emails per year for Netflix, Reddit, and Amazon
- Lowest cost per email among major providers with simple pay-as-you-go pricing
- Deep integration with the AWS ecosystem and SDKs in all major languages
- Highly scalable with no sending limits after warmup
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
- Setup is complex with documentation that can be difficult to navigate
- New accounts are sandboxed to 200 messages per 24-hour period
- Accessing analytics requires additional AWS services like SNS and Lambda
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 the difference between Amazon SES and Resend?
Amazon SES is a cost-effective, cloud-scale email service built on AWS infrastructure. Resend is a modern email API built for developers, with React Email support and a focus on simplicity. Amazon SES is best suited for cost-sensitive, high-volume, while Resend is geared toward developer-first, react teams.
Which is cheaper, Amazon SES or Resend?
3,000 free emails per month for the first 12 months. After that, $0.10 per 1,000 emails with additional charges for attachments and dedicated IPs. 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.
Which is faster, Amazon SES or Resend?
Based on real-world data from Knock, Amazon SES has a median API response time (p50) of 153ms compared to 81ms for Resend.
Which is more reliable, Amazon SES or Resend?
From February 10th to May 11th, Amazon SES showed an error rate of 0.00% while Resend showed 0.07%. Both rates are within acceptable thresholds for production email delivery, and Knock automatically retries failed requests to minimize the impact of transient errors.
Which is more popular, Amazon SES or Resend?
On the Knock platform, Amazon SES handled 25M–100M messages from February 10th to May 11th compared to 10M–25M for Resend. Amazon SES is currently seeing declining volume, while Resend volume has remained stable.
Can I use both Amazon SES and Resend together?
Yes. Knock enables you to integrate multiple email providers into a single notification workflow. You can use Amazon SES and Resend side by side, route traffic between them, or migrate from one to the other without changing your application code.
What are the main pros and cons of Amazon SES vs Resend?
Amazon SES strengths include delivers billions of emails per year for netflix, reddit, and amazon and lowest cost per email among major providers with simple pay-as-you-go pricing. 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, Amazon SES drawbacks include setup is complex with documentation that can be difficult to navigate, while Resend drawbacks include newer and less battle-tested compared to incumbents like mailgun or sendgrid.
Use either provider with Knock
Knock enables you to integrate Amazon SES, Resend, or any combination of email providers into a single notification workflow. Manage templates, orchestrate cross-channel delivery, and switch providers without changing your code.