Mailjet vs Sparkpost
Compare Mailjet 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) |
|---|---|---|---|---|
 | <1M | 6th of 10 ↓ | 0 | 0 |
 | <1M | 10th of 10 → | 3 | 11 |
From January 1st to March 31st, Knock routed <1M messages through Mailjet and <1M through Sparkpost. Mailjet reported 0 status page updates over the last 90 days, while Sparkpost reported 11.
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 1st to March 31st. The top-line number is an average of these daily values: Mailjet averaged 414ms compared to 287ms for Sparkpost. Mailjet's highest daily p50 was 490ms; Sparkpost's was 336ms. Sparkpost is 127ms 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, Mailjet has a p90 of 532ms compared to 346ms for Sparkpost. The highest daily p90 was 652ms for Mailjet and 402ms for Sparkpost. Sparkpost handles these slower requests 186ms 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, Mailjet reached 710ms at p99 while Sparkpost reached 542ms. The highest daily p99 was 5110ms for Mailjet and 31566ms for Sparkpost, indicating the worst-case response time during spikes or provider-side congestion. Sparkpost 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% | 0.12% | Feb 23 | 88 | 2 |
| 0.21% | 3.41% | Feb 24 | 89 | 1 |
Averaged across the date range, Mailjet shows a 0.00% daily error rate compared to 0.21% for Sparkpost. The highest single-day error rate was 0.12% for Mailjet and 3.41% for Sparkpost. Mailjet 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 Mailjet incidents
Recent status page incidents for Mailjet
No incidents reported in the last 90 days
Recent Sparkpost incidents
Recent status page incidents for Sparkpost
Started Mar 16, 2026 — Resolved Mar 16, 2026
Mar 16, 19:00 EDT Completed - The scheduled maintenance has been completed.Mar 16, 16:45 EDT Update - Scheduled maintenance is still in progress, the maintenance window has been extend by one hour to allow the maintenance to finish. During the full duration of this maintenance all emails will continued to be accepted. This maintenance only impacts our EU sending infrastructure.Mar 16, 15:00 EDT In progress - Scheduled maintenance is currently in progress. We will provide updates as necessary.
Started Mar 12, 2026 — Resolved Mar 12, 2026
Mar 12, 07:25 EDT Resolved - This incident has been resolved.Mar 12, 06:03 EDT Monitoring - System functionality has been fully restored and all emails are being transmitted correctly without added latencies; we are actively monitoring.Mar 12, 04:00 EDT Investigating - Email delivery in US is impacted, experiencing elevated delays.Mar 12, 03:48 EDT Monitoring - System is fully recovered and under monitoring.Mar 12, 02:51 EDT Investigating - We are currently investigating issues with delivery of
Started Mar 5, 2026 — Resolved Mar 5, 2026
Mar 4, 20:24 EST Resolved - This incident has been resolved.Mar 4, 20:00 EST Monitoring - We are observing recovery in email delivery performance and are actively monitoring.Mar 4, 19:51 EST Investigating - We are investigating an increase in delivery latency for some outbound messages.
Started Feb 27, 2026 — Resolved Feb 27, 2026
Feb 27, 12:38 EST Resolved - Microsoft has confirmed that they made additional changes the night of Thursday, Feb 26th that should have remediated most IP rate limiting and rejection issues. If you are still seeing impacts, please reach out via your normal support channels and our team can investigate and escalate with Microsoft.Feb 26, 12:55 EST Monitoring - We are currently seeing elevated temporary rejection rates for email delivered to Outlook.com, Hotmail, and other Microsoft-hosted addres
Started Feb 24, 2026 — Resolved Feb 24, 2026
Feb 24, 14:41 EST Resolved - This incident has been resolved.Feb 24, 14:38 EST Monitoring - A fix has been implemented and we are monitoring the results.Feb 24, 14:34 EST Identified - The team has identified the root cause. There is a core networking issue that has impacted sending across the clusters.Feb 24, 14:25 EST Update - We are continuing to investigate this issue. We still see 5xx errors on mail injections and degradation.Feb 24, 14:07 EST Update - We are continuing to investigate this
Pros and cons
Mailjet
Sparkpost
Pros
- Hybrid support for both marketers and developers in a single platform
- Unique real-time collaboration features for team-based template editing
- EU-only data processing for companies with strict data residency requirements
- Powers email delivery for over 130,000 companies including Microsoft and DHL
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
- Activated automation workflows cannot be edited, requiring new workflows for any changes
- Some analytics and deliverability tools are locked behind higher pricing plans
- Deliverability can lag behind specialists like Postmark
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 Mailjet and Sparkpost?
Mailjet is a collaborative email platform with real-time editing and combined transactional and marketing capabilities. SparkPost is a data-driven email delivery platform with advanced analytics and predictive tools for high-volume senders. Mailjet is best suited for team collaboration + marketing, while Sparkpost is geared toward data-driven, high-volume.
Which is cheaper, Mailjet or Sparkpost?
Free tier includes 200 emails per day (6,000/month). Paid plans start at $17/month for 15,000 emails with no daily limit. Premium plans start at $105/month for 100,000 emails. 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, Mailjet or Sparkpost?
Based on real-world data from Knock, Mailjet has a median API response time (p50) of 414ms compared to 287ms for Sparkpost.
Which is more reliable, Mailjet or Sparkpost?
From January 1st to March 31st, Mailjet showed an error rate of 0.00% while Sparkpost showed 0.21%. 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, Mailjet or Sparkpost?
On the Knock platform, Mailjet handled <1M messages from January 1st to March 31st compared to <1M for Sparkpost. Mailjet is currently seeing declining volume, while Sparkpost volume has remained stable.
Can I use both Mailjet and Sparkpost together?
Yes. Knock enables you to integrate multiple email providers into a single notification workflow. You can use Mailjet 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 Mailjet vs Sparkpost?
Mailjet strengths include hybrid support for both marketers and developers in a single platform and unique real-time collaboration features for team-based template editing. 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, Mailjet drawbacks include activated automation workflows cannot be edited, requiring new workflows for any changes, 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 Mailjet, 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.