Mermaid vs Resend

Two Tech stack tools side by side: what each does, what it costs and who it suits.

The verdict Side by side Plans and pricing Who each is for Other options

The verdict

On the data we hold, Resend comes out ahead. Here is why, point by point.

What the data says

Both have a free plan, so you can try each before you pay.
Mermaid starts lower, at $10/mo against $20/mo.
In our Tech stack ranking, Resend places 34 and Mermaid 15 of 72.

Side by side

Mermaid and Resend compared
At a glance	Mermaid	Resend
Starts at	$10/mo	$20/mo
Free plan	Yes	Yes
API	No	Yes
MCP server	Yes	Yes
Links	Visit	Visit

Plans and pricing

Mermaid

BasicFree plan with up to 3 diagrams, limited diagram size and limited AI.Free
PlusUnlimited diagrams and 300 AI credits a year; 10 per user per month billed annually.$120/yr/seat
Premium2,000 AI credits a year, free viewer seats and unlimited teams; 20 per user per month billed annually.$240/yr/seat

Resend

FreeFree forever: 3,000 emails per month (100 per day), 3 domains, 1 webhook endpoint.Free
Pro50,000 emails per month, then $0.90 per 1,000 extra; 10 domains and no daily limit.$20/mo
Scale100,000 emails per month, then $0.90 per 1,000 extra; 1,000 domains and a dedicated Slack channel.$90/mo

Prices as the vendors list them. They change often; the final price is on their sites.

Who each is for

Choose Mermaid if…

Developers, technical writers and operations teams who keep diagrams as text next to their code and docs, so they stay versioned and never turn into stale screenshots.

Visit Read the review

Choose Resend if…

Software teams that want to send transactional email, such as sign-ups, receipts and password resets, and some marketing email from their own code, with a clean API and good developer tooling.

Visit Read the review

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