A Resend-compatible API your existing code already speaks, plus the deliverability, observability, and white-label control most providers make you stitch together yourself. All of it runs on our own dedicated sending infrastructure — not a reseller layer on top of someone else's.
Drop-in for the resend SDK Inbox-grade deliverability White-label multi-tenancy
Point the resend SDK at our base URL and your code keeps working — same payloads, same response shapes. Migrate in one line, then grow into the superset.
Send with the exact Resend payload: from, to, cc, bcc, reply_to, subject, html, text, attachments, headers, and tags. Validation returns actionable errors, not 500s.
POST /emails/batch accepts up to a hundred messages in a single request — distinct recipients, subjects, and tags per entry — so high-volume jobs stay one round trip instead of a hundred.
Pass scheduled_at to queue a send for later, fetch it with GET /emails/:id, and cancel it before it leaves. Natural-language and ISO 8601 times both work.
Send the same Idempotency-Key header twice and the second request returns the first result instead of a duplicate email. Safe retries through any flaky network.
Send-accept lands at p99 under 300ms because we enqueue durably and return immediately. Your request thread never blocks on the actual delivery.
Official usermails SDKs, a documented resend drop-in via base-URL override, and SMTP relay credentials for the stacks that still speak SMTP.
Resend compatibility is a contract, not a one-time port. Features ship as a superset — your existing payloads never break.
Add a domain and we generate the keys and records that decide whether you reach the inbox — then verify them live.
We generate DKIM keys and derive the SPF, DMARC, optional MAIL FROM, and tracking CNAME records every authenticated sender needs — alignment included, no guesswork.
Publish records straight to supported DNS providers, or copy-paste them into any registrar. Live re-verification shows pending, verified, or failed per record.
We warn before you send on a misaligned or unverified domain, with DMARC policy guidance from none to quarantine to reject and a readiness checker — plus BIMI once you reach enforcement.
Credentials scoped to a single project, and a delivery path engineered so an accepted send is a kept promise.
Create and revoke keys per project, each scoped to exactly what it should touch. Keys are shown once and stored only as hashes — we can never reveal them back. Per-key rate limits and usage are visible at a glance.
Every send enters a durable queue before it leaves, with retry policies for transient failures and automatic suppression on hard bounce or complaint. No silent send loss, ever — accepted means delivered or accounted for.
Per-project suppression lists are enforced before a message is ever queued, so you can't re-mail an address that already bounced or complained — your reputation is protected by default.
Sensitive payload fields are encrypted at rest, keys live hashed, and every resource is isolated to its tenant at the data layer — not just hidden in the UI.
Every delivery, bounce, complaint, open, and click is captured — pushed to you signed, and queryable per message.
Register endpoints per project and subscribe to the event types you care about. Every payload is HMAC-signed so you can verify it came from us and nobody else.
At-least-once delivery with exponential backoff on failure, a full delivery log per endpoint, and one-click manual replay when your receiver was down.
Filter the email log by status, recipient, subject, tag, domain, and date — at high volume, backed by an analytics store built for the query load.
Open any message to see its full event timeline — queued, sent, delivered, opened, clicked — alongside the rendered content and raw headers.
When a send fails we tell you why in plain language — the bounce class, the suppression reason, the auth gap — so you fix the cause, not the symptom.
Sends, delivered, bounced, complained, opened, and clicked over time, with per-domain reputation summaries and bounce and complaint-rate alerts.
We run our own dedicated sending infrastructure, so we can see and steer reputation across every tenant — the things raw infrastructure can't do for you.
Shared pools for low volume, dedicated pools for scale — with transactional and marketing streams kept on separate reputations so one never poisons the other.
Ramp schedules that throttle volume per IP per day and auto-adjust to engagement and bounce signals — no spreadsheet, no manual babysitting.
Seed-list tests across major mailbox providers report exactly where your mail lands — inbox, spam, or missing — provider by provider.
Continuous monitoring of your sending IPs and domains against the major blocklists, plus a composite reputation score with trend and alerts.
We ingest your DMARC aggregate reports to surface who's sending as you and where alignment fails — and guide BIMI setup once you reach enforcement.
Signup screening, send-pattern anomaly detection, per-tenant caps, and a fast kill-switch — so shared infrastructure stays clean for everyone on it.
Multi-tenant from the schema up — organizations contain projects, projects scope every key, domain, log, and send. Isolation is enforced at the data layer, not the interface.
A clean tenancy spine with role-based access — owner, admin, developer, viewer — per org. Every resource belongs to exactly one project; no cross-tenant access is possible.
Your own dashboard domain, logo, and colors, with custom sending and tracking domains per org and a "powered by" toggle. Your customers see your brand, end to end.
List your sub-tenants, see per-tenant usage at a glance, and export billing-ready rollups — everything an agency or platform needs to charge for email it resells.
Transactional ships first because that's the acute pain. Lifecycle and marketing land on the very same events — one account, one stream, no second vendor.
A first-class contact store with dynamic segments built from the same activity and engagement signals your transactional sends already produce.
One-off and recurring campaigns with a block editor, templates, A/B testing, and one-click unsubscribe — sent through the same authenticated, warmed infrastructure.
Journeys triggered by the same event stream and your product events via the API and webhooks — welcome series, win-backs, and lifecycle flows without a separate tool.
Phased on purpose: a developer can fully migrate off Resend today, then turn on marketing when it ships — without re-platforming.
Create a project, verify a domain, drop in a key, and change one base URL. Free to start, no card required.
resend SDK compatible dedicated infrastructure inbox-grade deliverability