Mailgun vs Sparkpost
Compare Mailgun and Sparkpost 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 → | 4 | 13 |
| <1M | 10th of 10 → | 2 | 3 |
From May 24th to August 22nd, Knock routed 100M–500M messages through Mailgun and <1M through Sparkpost. Mailgun reported 13 status page updates over the last 90 days, while Sparkpost reported 3.
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 May 24th to August 22nd. The top-line number is an average of these daily values: Mailgun averaged 138ms compared to 278ms for Sparkpost. Mailgun's highest daily p50 was 167ms; Sparkpost's was 312ms. Mailgun is 140ms 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, Mailgun has a p90 of 197ms compared to 506ms for Sparkpost. The highest daily p90 was 8262ms for Mailgun and 574ms for Sparkpost. Mailgun handles these slower requests 309ms 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 582ms at p99 while Sparkpost reached 612ms. The highest daily p99 was 15385ms for Mailgun and 766ms for Sparkpost, indicating the worst-case response time during spikes or provider-side congestion. Both providers exhibit comparable tail response times, meaning neither is significantly more prone to outlier slowdowns.
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% | 0.04% | Jun 23 | 89 | 2 |
| 0.00% | 0.00% | May 24 | 91 | 0 |
Averaged across the date range, Mailgun shows a 0.00% daily error rate compared to 0.00% for Sparkpost. The highest single-day error rate was 0.04% for Mailgun and 0.00% for Sparkpost. 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 Aug 20, 2026 — Resolved Aug 20, 2026
Aug 20, 10:31 PDT Resolved - This incident has been resolved. Aug 20, 10:09 PDT Update - GCP has put a mitigation in place, we are monitoring the results. At this time we are experiencing no impacts. All delayed webhooks and logs have been processed. Aug 20, 09:30 PDT Update - Outbound delivery is operating normally. Currently there are delays for event logs and some webhooks. Aug 20, 09:19 PDT Monitoring - Mailgun is monitoring service impacts in GCP's us-west1 region. We are routing
Started Aug 17, 2026 — Resolved Aug 17, 2026
Aug 17, 13:18 PDT Resolved - We have received confirmation that an external issue impacting email delivery to Microsoft 365 domains has been resolved. Impacted messages would have received an error stating "5.7.511 Access denied, banned sender" between Friday, August 14th and Monday, August 17th. Any failed messages will need to be resent. Information on retrying messages can be found in our Help Center here: https://help.mailgun.com/hc/en-us/articles/18596982041883-Resending-messages
Started Aug 11, 2026 — Resolved Aug 11, 2026
Aug 11, 00:07 PDT Resolved - This incident has been resolved. Aug 10, 23:54 PDT Monitoring - A fix has been implemented and we are monitoring the results. Aug 10, 22:32 PDT Identified - The issue has been identified and a fix is being implemented. Aug 10, 22:32 PDT Investigating - We are currently experiencing a denial of service attack against our click and open tracking servers in our US regions. Remediation work is underway. Some requests may time out or fail at this time.
Started Jul 24, 2026 — Resolved Jul 24, 2026
Jul 24, 06:49 PDT Resolved - All delayed messages have been processed. Systems are operating normally Jul 24, 06:18 PDT Monitoring - A fix has been implemented and we are monitoring the results. Delayed messages are being processed. Jul 24, 06:16 PDT Update - We are continuing to work on a fix for this issue. Jul 24, 05:38 PDT Identified - The issue has been identified and a fix is being implemented. Jul 24, 05:27 PDT Investigating - Inbound messages processed by routes are currentl
Started Jul 13, 2026 — Resolved Jul 13, 2026
Jul 13, 12:56 PDT Resolved - This incident has been resolved. Jul 13, 12:45 PDT Monitoring - A fix has been implemented and we are monitoring the results. Jul 13, 12:24 PDT Identified - The issue has been identified and a fix is being implemented. Jul 13, 11:51 PDT Update - We are continuing to investigate this issue. Jul 13, 11:23 PDT Investigating - We are currently investigating this issue.
Recent Sparkpost incidents
Recent status page incidents for Sparkpost
Started Aug 19, 2026 — Resolved Aug 19, 2026
Aug 19, 15:58 EDT Resolved - This incident has been resolved. Aug 19, 15:44 EDT Monitoring - A fix has been implemented and we are monitoring the results. Aug 19, 14:52 EDT Investigating - We are investigating an increase in delivery latency for some outbound messages. (NOTE: This does not impact our customers hosted in the US.)
Started Jul 24, 2026 — Resolved Jul 24, 2026
Jul 24, 14:44 EDT Resolved - This incident has been resolved. Jul 24, 13:29 EDT Update - We have implemented additional tuning to handle the significant influx of mail due to the AWS network outage and we are seeing improvement in delivery rates We are seeing significant recovery and expect most mail to be fully delivered in the next 30-35 minutes. Estimated time for full recovery is 80-90 minutes. We are continuing to look for additional optimizations and monitor the issue. Jul 24, 09
Started Jun 29, 2026 — Resolved Jun 29, 2026
Jun 29, 12:46 EDT Resolved - This incident has been resolved. Jun 29, 12:05 EDT Monitoring - There was a combination of events that caused a short period of slowdown. That slowdown has already recovered and we are monitoring to ensure we do not see it again. Jun 29, 11:58 EDT Investigating - We are investigating the delay and the impact. We will post once we know more.
Pros and cons
Mailgun
Sparkpost
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
- Delivers nearly 40% of all commercial email worldwide
- Subaccount support for isolated sending streams under one billing account
- On-premise mail sending solution available for very high volume workloads
- Great analytics tools with predictive health scores for email deliverability
Cons
- Requires familiarity with email protocols and API integrations
- Pricing tiers can be confusing
- Email template features are basic without the Mailjet editor
Cons
- Documentation can be hard to navigate with less beginner-friendly getting started content
- Higher price point than basic providers
- Now part of Bird (formerly MessageBird), which may affect product direction
Frequently asked questions
What is the difference between Mailgun and Sparkpost?
Mailgun is a developer-focused email API platform owned by Sinch, known for flexible sending and receiving capabilities. SparkPost is a data-driven email delivery platform with advanced analytics and predictive tools for high-volume senders. Mailgun is best suited for developer-focused sending + receiving, while Sparkpost is geared toward data-driven, high-volume.
Which is cheaper, Mailgun or Sparkpost?
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. Free tier includes 500 emails per month with community support. Paid plans start at $20/month for 50,000 emails with premium deliverability features. 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 Sparkpost?
Based on real-world data from Knock, Mailgun has a median API response time (p50) of 138ms compared to 278ms for Sparkpost.
Which is more reliable, Mailgun or Sparkpost?
From May 24th to August 22nd, Mailgun showed an error rate of 0.00% while Sparkpost 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.
Which is more popular, Mailgun or Sparkpost?
On the Knock platform, Mailgun handled 100M–500M messages from May 24th to August 22nd compared to <1M for Sparkpost. Mailgun volume has remained stable, while Sparkpost volume has remained stable.
Can I use both Mailgun and Sparkpost together?
Yes. Knock enables you to integrate multiple email providers into a single notification workflow. You can use Mailgun and Sparkpost 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 Sparkpost?
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. Sparkpost strengths include delivers nearly 40% of all commercial email worldwide and subaccount support for isolated sending streams under one billing account. On the other hand, Mailgun drawbacks include requires familiarity with email protocols and api integrations, while Sparkpost drawbacks include documentation can be hard to navigate with less beginner-friendly getting started content.
Use either provider with Knock
Knock enables you to integrate Mailgun, Sparkpost, or any combination of email providers into a single notification workflow. Manage templates, orchestrate cross-channel delivery, and switch providers without changing your code.