Mailtrap vs Mandrill
Compare Mailtrap and Mandrill 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) |
|---|---|---|---|---|
| <1M | 9th of 10 ↓ | 1 | 5 |
| <1M | 8th of 10 ↑ | 0 | 0 |
From July 24th to October 22nd, Knock routed <1M messages through Mailtrap and <1M through Mandrill. Mailtrap reported 5 status page updates over the last 90 days, while Mandrill reported 0.
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 July 24th to October 22nd. The top-line number is an average of these daily values: Mailtrap averaged 81ms compared to 338ms for Mandrill. Mailtrap's highest daily p50 was 218ms; Mandrill's was 535ms. Mailtrap is 257ms 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, Mailtrap has a p90 of 163ms compared to 641ms for Mandrill. The highest daily p90 was 907ms for Mailtrap and 1781ms for Mandrill. Mailtrap handles these slower requests 478ms 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, Mailtrap reached 755ms at p99 while Mandrill reached 1686ms. The highest daily p99 was 1675ms for Mailtrap and 10903ms for Mandrill, indicating the worst-case response time during spikes or provider-side congestion. Mailtrap 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% | 0.07% | Aug 1 | 90 | 1 |
| 0.00% | 0.08% | Sep 15 | 89 | 2 |
Averaged across the date range, Mailtrap shows a 0.00% daily error rate compared to 0.00% for Mandrill. The highest single-day error rate was 0.07% for Mailtrap This peak coincided with a major incident reported on Mailtrap's status page (Sending Services Downtime). and 0.08% for Mandrill. 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 Mailtrap incidents
Recent status page incidents for Mailtrap
Started Oct 8, 2026 — Resolved Oct 8, 2026
The maintenance is now complete. Thanks for your patience.
Started Aug 1, 2026 — Resolved Aug 1, 2026
Pingdom says we are back online.
Recent Mandrill incidents
Recent status page incidents for Mandrill
No incidents reported in the last 90 days
Pros and cons
Mailtrap
Mandrill
Pros
- Strong deliverability with dedicated IPs, auto warmup, and automatic authentication
- Great developer experience with comprehensive docs and MCP support for IDEs
- Combined testing sandbox and production sending in one platform
- Trusted by PayPal, Atlassian, Adobe, and Yelp
Pros
- Friendly, well-laid-out developer documentation that makes integration straightforward
- Global infrastructure for fast delivery with dedicated IPs and IP address pools
- Solid analytics with reports on deliverability, opens, clicks, bounces, and rejections
- Reuse Mailchimp templates for transactional email with deep ecosystem integration
Cons
- Native integration ecosystem is smaller than established competitors
- Lower sending limits on free tier compared to some providers
- No rate limits by default, which may require custom throttling configuration
Cons
- Requires an existing Mailchimp Standard or Premium subscription
- Not available as a standalone service
- Higher cost than some dedicated transactional services
Frequently asked questions
Mailtrap is an email platform combining safe testing and sandbox environments with production sending capabilities. Mandrill is a transactional email add-on for Mailchimp, suited for teams already using the Mailchimp platform. Mailtrap is best suited for email testing + qa, while Mandrill is geared toward mailchimp users needing transactional.
Free tier includes 4,000 emails per month (150/day limit). Paid plans start at $15/month for 10,000 emails with overages at $1.00/1K. Included as an add-on to Mailchimp Standard or Premium plans. Pricing is based on email blocks of 25,000 emails, starting at $20/block. Volume discounts apply: $18/block above 500K, scaling down to $10/block above 4M. 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, Mailtrap has a median API response time (p50) of 81ms compared to 338ms for Mandrill.
From July 24th to October 22nd, Mailtrap showed an error rate of 0.00% while Mandrill 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, Mailtrap handled <1M messages from July 24th to October 22nd compared to <1M for Mandrill. Mailtrap is currently seeing declining volume, while Mandrill is trending upward.
Yes. Knock enables you to integrate multiple email providers into a single notification workflow. You can use Mailtrap and Mandrill side by side, route traffic between them, or migrate from one to the other without changing your application code.
Mailtrap strengths include strong deliverability with dedicated ips, auto warmup, and automatic authentication and great developer experience with comprehensive docs and mcp support for ides. Mandrill strengths include friendly, well-laid-out developer documentation that makes integration straightforward and global infrastructure for fast delivery with dedicated ips and ip address pools. On the other hand, Mailtrap drawbacks include native integration ecosystem is smaller than established competitors, while Mandrill drawbacks include requires an existing mailchimp standard or premium subscription.
Use either provider with Knock
Knock enables you to integrate Mailtrap, Mandrill, or any combination of email providers into a single notification workflow. Manage templates, orchestrate cross-channel delivery, and switch providers without changing your code.