Mailgun vs Mandrill
Compare Mailgun 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) |
|---|---|---|---|---|
| 100M–500M | 5th of 10 → | 5 | 9 |
| 1M–10M | 9th of 10 ↓ | 0 | 0 |
From March 24th to June 22nd, Knock routed 100M–500M messages through Mailgun and 1M–10M through Mandrill. Mailgun reported 9 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 March 24th to June 22nd. The top-line number is an average of these daily values: Mailgun averaged 133ms compared to 137ms for Mandrill. Mailgun's highest daily p50 was 149ms; Mandrill's was 263ms. Both providers deliver comparable response times for the typical request.
The 90th percentile (p90) captures the slowest 10% of requests, revealing how each provider handles moderate stress. Averaged across all days, Mailgun has a p90 of 187ms compared to 358ms for Mandrill. The highest daily p90 was 829ms for Mailgun and 524ms for Mandrill. Mailgun handles these slower requests 171ms 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, Mailgun reached 483ms at p99 while Mandrill reached 857ms. The highest daily p99 was 3152ms for Mailgun and 1341ms for Mandrill, indicating the worst-case response time during spikes or provider-side congestion. Mailgun 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% | Mar 24 | 91 | 0 |
| 0.01% | 0.43% | Apr 27 | 83 | 7 |
Averaged across the date range, Mailgun shows a 0.00% daily error rate compared to 0.01% for Mandrill. The highest single-day error rate was 0.00% for Mailgun and 0.43% 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 Mailgun incidents
Recent status page incidents for Mailgun
Started Jun 18, 2026 — Resolved Jun 18, 2026
Jun 18, 03:24 PDT Resolved - This incident has been resolved. Jun 18, 03:11 PDT Monitoring - A fix has been implemented and we are monitoring the results. Jun 18, 02:53 PDT Identified - The issue has been identified and a fix is being implemented. Jun 18, 02:11 PDT Update - We are continuing to investigate this issue. Jun 18, 01:34 PDT Investigating - Customers using the events/logs APIs or viewing logs in the customer portal may see delays in some events appearing. These delays are
Started Jun 16, 2026 — Resolved Jun 16, 2026
Jun 16, 10:34 PDT Resolved - This incident has been resolved. Jun 16, 09:16 PDT Monitoring - A fix has been implemented and we are monitoring the results. Jun 16, 08:48 PDT Update - We are continuing to investigate this issue. Jun 16, 08:08 PDT Update - We are continuing to investigate this issue. Jun 16, 07:28 PDT Investigating - Logs are currently experiencing delays of 15 minutes in Mailgun's US region. Outbound processing, inbound processing, and webhook delivery are operating n
Started Jun 5, 2026 — Resolved Jun 5, 2026
Jun 5, 07:15 PDT Resolved - This incident has been resolved. Jun 5, 07:04 PDT Monitoring - A fix has been implemented and we are monitoring results. Outbound processing, inbound processing, and webhook delivery continue operating normally. Jun 5, 06:26 PDT Investigating - Logs are currently experiencing delays of 15 minutes in Mailgun's US region. Outbound processing, inbound processing, and webhook delivery are operating normally.
Started Jun 4, 2026 — Resolved Jun 4, 2026
Jun 4, 14:04 PDT Resolved - This incident has been resolved. Jun 4, 13:48 PDT Monitoring - Logs are flowing normally and engineers continue to monitor. Jun 4, 12:52 PDT Update - We are continuing to investigate this issue. Outbound processing, inbound processing, and webhook delivery continue to operate normally. Jun 4, 11:42 PDT Update - We are continuing to investigate this issue. Jun 4, 11:01 PDT Investigating - Logs are currently experiencing delays of 15 minutes in Mailgun
Started May 25, 2026 — Resolved May 25, 2026
May 25, 08:55 PDT Resolved - This incident has been resolved. May 25, 08:45 PDT Monitoring - A fix has been implemented and we are monitoring the results. May 25, 08:35 PDT Update - We are continuing to work on a fix for this issue. May 25, 07:46 PDT Identified - The issue has been identified and a fix is being implemented. May 25, 07:10 PDT Update - We are continuing to investigate this issue. May 25, 06:38 PDT Investigating - We are currently investigating this issue. May 25,
Recent Mandrill incidents
Recent status page incidents for Mandrill
No incidents reported in the last 90 days
Pros and cons
Mailgun
Mandrill
Pros
- Well-written documentation with comprehensive guides and best practices for deliverability
- Robust deliverability support with optional expert pairing to optimize sending
- Powerful inbound email processing with customizable routing rules
- Trusted by Lyft, American Express, and Wikipedia since 2010
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
- Requires familiarity with email protocols and API integrations
- Pricing tiers can be confusing
- Email template features are basic without the Mailjet editor
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
What is the difference between Mailgun and Mandrill?
Mailgun is a developer-focused email API platform owned by Sinch, known for flexible sending and receiving capabilities. Mandrill is a transactional email add-on for Mailchimp, suited for teams already using the Mailchimp platform. Mailgun is best suited for developer-focused sending + receiving, while Mandrill is geared toward mailchimp users needing transactional.
Which is cheaper, Mailgun or Mandrill?
Free tier includes 100 emails per day with no expiration. Paid plans start at $15/month for 10,000 emails with overages at $1.80/1K. 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.
Which is faster, Mailgun or Mandrill?
Based on real-world data from Knock, Mailgun has a median API response time (p50) of 133ms compared to 137ms for Mandrill.
Which is more reliable, Mailgun or Mandrill?
From March 24th to June 22nd, Mailgun showed an error rate of 0.00% while Mandrill showed 0.01%. 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, Mailgun or Mandrill?
On the Knock platform, Mailgun handled 100M–500M messages from March 24th to June 22nd compared to 1M–10M for Mandrill. Mailgun volume has remained stable, while Mandrill is seeing declining volume.
Can I use both Mailgun and Mandrill together?
Yes. Knock enables you to integrate multiple email providers into a single notification workflow. You can use Mailgun and Mandrill 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 Mailgun vs Mandrill?
Mailgun strengths include well-written documentation with comprehensive guides and best practices for deliverability and robust deliverability support with optional expert pairing to optimize sending. 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, Mailgun drawbacks include requires familiarity with email protocols and api integrations, while Mandrill drawbacks include requires an existing mailchimp standard or premium subscription.
Use either provider with Knock
Knock enables you to integrate Mailgun, 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.