Resend vs Polar
The email API for developers — built by the Nodemailer team
vs. Merchant of Record for devs — usage-based billing, MoR, 4% + 40¢
Pricing tiers
Resend
Free
3,000 emails/month, 100 emails/day. 1 custom domain. Ideal for side projects.
Free
Pro — 50k
50,000 emails/month. 10 custom domains. Priority support.
$20/mo
Pro — 100k
100,000 emails/month. 10 custom domains.
$35/mo
Scale — 100k+
Tiered from 100k → 2.5M emails/month. Dedicated IP add-on available.
$90/mo
Scale — 2.5M
2.5M emails/month.
$1150/mo
Enterprise
3M+/month, dedicated IP included, SSO, custom contract.
Custom
Polar
Pay-as-you-go
4% + 40¢ per transaction. Cheapest Merchant-of-Record. No monthly or setup fees.
$0 base (usage-based)
Enterprise
Custom. Volume discounts for high-growth teams.
Custom
Free-tier quotas head-to-head
Comparing free on Resend vs payg on Polar.
| Metric | Resend | Polar |
|---|---|---|
| custom domains | 1 domains | — |
| emails per day | 100 emails/day | — |
| emails per month | 3000 emails/month | — |
Features
Resend · 12 features
- Audiences — Contact list management with custom fields.
- Batch Send — Send up to 100 emails in one API call.
- Broadcasts — Bulk email campaigns with audiences, A/B testing, analytics.
- Dedicated IP — Add-on for high-volume senders. Auto warmup.
- Domains — DKIM/SPF/DMARC auto-verification. Per-domain analytics.
- Idempotency — Prevent duplicate sends with Idempotency-Key header.
- Logs + Analytics — Full email logs, delivery heatmap, events table.
- React Email — OSS library (3M+ downloads) to compose emails in React/JSX.
- Scheduled Send — scheduledAt parameter for future delivery.
- Send API — POST /emails endpoint to send. Supports attachments, scheduled send, idempotency…
- Suppressions — Auto-managed bounce + complaint list. API to add/remove.
- Webhooks — Email lifecycle events: sent, delivered, bounced, complained, opened, clicked.
Polar · 15 features
- Customer Portal — Self-serve subscription management.
- Feature Flags — Simple flag mgmt tied to subscription tiers.
- Framework Adapters — Next.js, BetterAuth, TS, Python, Laravel, Ruby, 11+ more.
- Fraud Protection — Chargeback + fraud handling included.
- GitHub Sponsors Import — Import existing sponsors to Polar.
- Global Tax Compliance — VAT/GST/sales tax filed by Polar.
- Hosted Checkout — Polar-hosted + embeddable checkout.
- License Keys — Generate + validate license keys for software.
- Metering — Track API calls, tokens, custom units.
- One-off Purchases — Single purchases + digital downloads.
- Open-Source Backend — Full platform code on GitHub.
- Sandbox Environment — Test transactions without charging.
- Subscriptions — Tiered plans with upgrades/downgrades.
- Usage-Based Billing — Event ingestion → meter → invoice.
- Webhooks — Resource events with HMAC signatures.
Developer interfaces
| Kind | Resend | Polar |
|---|---|---|
| CLI | Resend CLI | — |
| SDK | react-email, resend-go, resend-node, resend-php, resend-python, resend-ruby | polar-sdk-python, @polar-sh/better-auth, @polar-sh/nextjs, @polar-sh/sdk |
| REST | Resend REST API | Polar REST API |
| MCP | — | Polar MCP |
| OTHER | SMTP Relay, Webhooks (Svix) | Polar Checkout, Polar Webhooks |
Staxly is an independent catalog of developer platforms. Some links to Resend and Polar may be affiliate links — Staxly may earn a commission if you sign up through them, at no extra cost to you. Pricing is verified against vendor pages at publication time — reconfirm before buying.
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