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 ↑ | 0 | 0 | |
<1M | 10th of 10 → | 0 | 0 |
From January 22nd to April 22nd, Knock routed 100M–500M messages through Mailgun and <1M through Sparkpost. Mailgun reported 0 status page updates over the last 90 days, while Sparkpost 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 January 22nd to April 22nd. The top-line number is an average of these daily values: Mailgun averaged 127ms compared to 285ms for Sparkpost. Mailgun's highest daily p50 was 147ms; Sparkpost's was 336ms. Mailgun is 158ms 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 184ms compared to 348ms for Sparkpost. The highest daily p90 was 220ms for Mailgun and 402ms for Sparkpost. Mailgun handles these slower requests 164ms 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 382ms at p99 while Sparkpost reached 551ms. The highest daily p99 was 481ms for Mailgun and 31566ms for Sparkpost, 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% | 0.03% | Mar 17 | 90 | 1 | |
0.19% | 3.41% | Feb 24 | 90 | 1 |
Averaged across the date range, Mailgun shows a 0.00% daily error rate compared to 0.19% for Sparkpost. The highest single-day error rate was 0.03% for Mailgun and 3.41% for Sparkpost. Mailgun 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 Mailgun incidents
Recent status page incidents for Mailgun
No incidents reported in the last 90 days
Recent Sparkpost incidents
Recent status page incidents for Sparkpost
No incidents reported in the last 90 days
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 127ms compared to 285ms for Sparkpost.
Which is more reliable, Mailgun or Sparkpost?
From January 22nd to April 22nd, Mailgun showed an error rate of 0.00% while Sparkpost showed 0.19%. 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 January 22nd to April 22nd compared to <1M for Sparkpost. Mailgun is currently trending upward in adoption, 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.