MailerSend vs SendGrid
Compare MailerSend and SendGrid 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 | 7th of 10 → | 0 | 1 | |
100M–500M | 2nd of 10 → | 25 | 25 |
From June 12th to September 10th, Knock routed <1M messages through MailerSend and 100M–500M through SendGrid. MailerSend reported 1 status page update over the last 90 days, while SendGrid reported 25.
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.
| Provider | Median (p50) | p90 | p95 | p99 |
|---|---|---|---|---|
110ms | 307ms | 359ms | 739ms | |
15ms | 35ms | 44ms | 107ms |
The chart above shows each provider's daily median response time (p50) from June 12th to September 10th. The top-line number is an average of these daily values: MailerSend averaged 110ms compared to 15ms for SendGrid. MailerSend's highest daily p50 was 724ms; SendGrid's was 21ms. SendGrid is 95ms 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, MailerSend has a p90 of 307ms compared to 35ms for SendGrid. The highest daily p90 was 3166ms for MailerSend and 66ms for SendGrid. SendGrid handles these slower requests 272ms 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, MailerSend reached 739ms at p99 while SendGrid reached 107ms. The highest daily p99 was 24436ms for MailerSend and 148ms for SendGrid, indicating the worst-case response time during spikes or provider-side congestion. SendGrid 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% | 0.27% | Jul 21 | 90 | 1 | |
0.00% | 0.00% | Jun 12 | 91 | 0 |
Averaged across the date range, MailerSend shows a 0.00% daily error rate compared to 0.00% for SendGrid. The highest single-day error rate was 0.27% for MailerSend and 0.00% for SendGrid. 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 MailerSend incidents
Recent status page incidents for MailerSend
Started Jul 1, 2026 — Resolved Jul 1, 2026
Status: Complete Maintenance has completed Affected components SMTP (Under maintenance) Delivery time (Under maintenance) Email sending API (Under maintenance) Bulk endpoint (Under maintenance)
Recent SendGrid incidents
Recent status page incidents for SendGrid
Ongoing since Oct 29, 2026
THIS IS A SCHEDULED EVENT Oct 28, 20:00 PDT - Oct 29, 00:00 PDT Sep 4, 00:24 PDT Scheduled - Twilio is conducting a planned maintenance from 28 October 2026 at 20:00 PDT until 29 October 2026 at 00:00 PDT. During the maintenance window, there could be intermittent delays or failures delivering SMS and MMS to and from United States and Canada handsets when sending via long codes, short codes and toll free numbers.
Ongoing since Oct 22, 2026
THIS IS A SCHEDULED EVENT Oct 21, 20:00 PDT - Oct 22, 00:00 PDT Sep 4, 00:24 PDT Scheduled - Twilio is conducting a planned maintenance from 21 October 2026 at 20:00 PDT until 22 October 2026 at 00:00 PDT. During the maintenance window, there could be intermittent delays or failures delivering SMS and MMS to and from United States and Canada handsets when sending via long codes, short codes and toll free numbers.
Ongoing since Oct 16, 2026
THIS IS A SCHEDULED EVENT Oct 16, 14:00 - 22:00 PDT Jul 29, 00:27 PDT Scheduled - Twilio will perform scheduled network maintenance in our IE1 region during an 8-hour window from 16 October 2026 at 14:00 PDT to 16 October 2026 at 22:00 PDT. During this window, customers may experience a brief service interruption of up to 90 seconds affecting the following: Interconnected Customers: All IE1 interconnected customers will experience a brief interconnection service interruption of up to 90 seco
Ongoing since Oct 15, 2026
THIS IS A SCHEDULED EVENT Oct 14, 22:00 PDT - Oct 15, 04:00 PDT Sep 4, 13:02 PDT Scheduled - Our SMS carrier partner in the United States and Canada is conducting a planned maintenance from 14 October 2026 at 22:00 PDT until 15 October 2026 at 04:00 PDT. During the maintenance window, there could be intermittent delays delivering SMS to and from United States and Canada handsets via United States and Canada long codes.
Ongoing since Oct 15, 2026
THIS IS A SCHEDULED EVENT Oct 14, 20:00 PDT - Oct 15, 00:00 PDT Sep 4, 00:23 PDT Scheduled - Twilio is conducting a planned maintenance from 14 October 2026 at 20:00 PDT until 15 October 2026 at 00:00 PDT. During the maintenance window, there could be intermittent delays or failures delivering SMS and MMS to and from United States and Canada handsets when sending via long codes, short codes and toll free numbers.
Pros and cons

MailerSend

SendGrid
Pros
- Designed for both developers and business users with API and visual editor
- Modern, intuitive UI that is easier to navigate than older platforms
- Multi-channel support with native email and SMS transactional messaging
- Affordable Hobby plan at $7/month for 5,000 emails with low overage rates
Pros
- Comprehensive documentation with SDKs for most major languages
- Rich analytics tools with programmatic API access to engagement data
- Strong focus on deliverability with AI-powered intelligent delivery
- Trusted by Uber, Booking.com, and Yelp for high-volume sending
Cons
- Available integrations with other tools are basic and limited
- Fewer advanced features than enterprise platforms
- Smaller ecosystem compared to established competitors
Cons
- Extended email activity history requires a paid add-on
- Pricing can become complex at higher volumes
- Support response times vary by plan tier
Frequently asked questions
What is the difference between MailerSend and SendGrid?
Mailersend is an intuitive transactional email and SMS service by Mailgun, designed for growing businesses. SendGrid is a cloud-based email delivery platform owned by Twilio, known for high-volume transactional and marketing email. MailerSend is best suited for growing saas + e-commerce, while SendGrid is geared toward high-volume transactional + marketing.
Which is cheaper, MailerSend or SendGrid?
Free tier includes 500 emails per month. Paid plans start at $7/month for 5,000 emails on the Hobby plan, with the Starter plan at $35/month for 50,000 emails. Free tier includes up to 100 emails per day for 60 days. Paid plans start at $19.95/month for 50,000 emails on the Essentials plan, with an Essentials 100K tier at $34.95/month. Pro plans with dedicated IPs start at $249/month for 300,000 emails. The best value depends on your sending volume. Use the pricing calculator above to compare costs at your expected volume.
Which is faster, MailerSend or SendGrid?
Based on real-world data from Knock, MailerSend has a median API response time (p50) of 110ms compared to 15ms for SendGrid.
Which is more reliable, MailerSend or SendGrid?
From June 12th to September 10th, MailerSend showed an error rate of 0.00% while SendGrid 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, MailerSend or SendGrid?
On the Knock platform, MailerSend handled <1M messages from June 12th to September 10th compared to 100M–500M for SendGrid. MailerSend volume has remained stable, while SendGrid volume has remained stable.
Can I use both MailerSend and SendGrid together?
Yes. Knock enables you to integrate multiple email providers into a single notification workflow. You can use MailerSend and SendGrid 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 MailerSend vs SendGrid?
MailerSend strengths include designed for both developers and business users with api and visual editor and modern, intuitive ui that is easier to navigate than older platforms. SendGrid strengths include comprehensive documentation with sdks for most major languages and rich analytics tools with programmatic api access to engagement data. On the other hand, MailerSend drawbacks include available integrations with other tools are basic and limited, while SendGrid drawbacks include extended email activity history requires a paid add-on.
Use either provider with Knock
Knock enables you to integrate MailerSend, SendGrid, or any combination of email providers into a single notification workflow. Manage templates, orchestrate cross-channel delivery, and switch providers without changing your code.