Good questions. Clear answers.

Send to documented sandbox addresses such as delivered@messagebird.dev, bounce@messagebird.dev or complaint@messagebird.dev. These exercise outcomes and webhooks through the normal pipeline. Keep a rehearsal audience limited to sandbox addresses; real addresses in the same send receive real mail.

The onboarding domain supports a first send under its documented restrictions, and sandbox addresses support testing. Verify your own sending domain for regular sending. Check your workspace’s current limits rather than relying on a fixed plan allowance on this page.

Use the first-email quickstart for an API integration, the SMTP guide for an existing SMTP application, Email marketing for campaigns, or the agent-mailbox quickstart for conversations. Each path links to the matching setup and documentation.

The Free plan gives you 1,000 emails a month at no cost and no card required. On the paid plans the per-message rate drops as you scale, and going over what your plan covers is billed per 1,000 emails. The pricing page carries the published figure for every step. An enterprise agreement can lift that cap entirely.

Downgrading does not break anything: handles you have already claimed keep working, you just cannot claim new ones until you are back under the allowance. A mailbox on your own domain counts toward your overall mailbox quota like any other, and its local part never touches the custom-handle allowance.

Dedicated IPs are an add-on on the Growth plan, up to five, at the monthly price shown on the email pricing page. There is no setup fee and no annual commitment.

Your effective rate limits depend on your organization’s plan and any configured override. Read the organization rate-limits endpoint or the response headers, and honor Retry-After when a request is limited. REST sending and SMTP share sending capacity; batches have a separate request policy. Starting a broadcast uses its campaign operation, while sending allowances and delivery pacing remain separate controls.

The estimated generated message must fit within 20 MB, including the HTML, text and base64-encoded attachments. Keep raw attachment content well below 15 MB to leave space for encoding and the rest of the message. A recipient’s server may apply a smaller limit.

When content storage is enabled, original sent-message bodies and attachments are available for up to 30 days. Mailbox headers, extracted text and mailbox attachments follow the selected 30-, 90- or 365-day retention tier available on your plan. Original mailbox bodies and received raw MIME remain limited to 30 days.

Grant only the permissions its job requires. Let it prepare and inspect a draft, then review the recipients, sender and content before authorizing a send. Rate limits help manage capacity; permissions and your review process control what the agent may do.

Yes, both go through the same send API. The only difference is the category field, which decides how suppressions and unsubscribes apply. Pick transactional for password resets and receipts, and marketing for campaigns.

Send an Idempotency-Key header with each logical send. If the first request succeeded but you never saw the response, replaying it with the same key gives you the original result back with an Idempotency-Replay header, rather than sending the email twice.

Set scheduled_at to any time between 30 seconds and 30 days ahead. The send comes back accepted straight away and stays scheduled until it goes out, so you can cancel it at any point before then.

Yes, as base64 in the attachments array. To show an image inline, give it a content_id and reference that from your HTML with cid:. Keep the raw files at or below 15 MB so the message still fits the 20 MB cap once it is encoded, and note that executable and script content types are refused before the send.

Yes. Applications that submit mail to an SMTP relay can use Bird by updating their host, port and credentials. Verify the sending domain and use an API key with email sending enabled.

Use port 465 for implicit TLS, or ports 587 and 2525 for STARTTLS. Select the host for your API key region. Port 25 is not offered for submission.

SMTP suits existing applications that already build MIME messages. The HTTP API provides structured request fields and stored-template operations. Both use the same domain, reputation and delivery controls.

Consult the published email pricing for your sending requirements. Our team can help with high-volume or migration requirements; a separate SMTP protocol does not require a separate email product.

Contacts belong to a workspace. A record can hold an email address, a phone number or both, plus an external ID and typed properties. Audiences reference those records, so updating a contact keeps its data consistent across the lists it belongs to.

Upload a CSV, TSV or Excel file in the dashboard and review the field mapping before importing. You can assign contacts to audiences during import. For application syncs, batch-upsert up to 1,000 contacts per request through the API or CLI.

The documented audience workflow uses static membership: you add or remove contacts. A broadcast resolves the audience when sending begins. Use your application or import workflow to keep membership current.

Define text, number, boolean and datetime properties with optional fallback values. Use those properties for recipient personalization and keep the typed values consistent when importing or syncing contacts.

Choose one saved audience. Bird resolves its current members when sending begins and applies the relevant suppressions and preferences. A template personalizes the message using each recipient’s registered contact properties.

Yes. The dashboard supports sending now or scheduling up to a year ahead, with editing and rescheduling before sending starts. Cancel a scheduled or sending broadcast to stop recipients it has not reached; messages already on their way cannot be recalled.

Broadcasts schedule a campaign for an audience. The messages API schedules inline content or a stored template from 30 seconds to 30 days ahead with scheduled_at. Bird pins the template version, language and parameter values at acceptance, then rejects the send if the template is deleted before it is due.

Create a separate audience containing only documented sandbox addresses. The simulated outcomes exercise delivery events and webhooks without external delivery. Sandbox traffic still uses sending allowance and appears in metrics.

Email marketing uses the dashboard’s broadcast composer on the same sending infrastructure as transactional email. Prepare an audience, write or choose content, review the sender and schedule the campaign. Developers can use the CLI and MCP workflow as well.

Use the marketing category for campaigns and send to people who asked to receive them. Bird applies recipient suppressions and opt-out preferences. Marketing email supports one-click unsubscribe headers and a link in the body; domain authentication and healthy lists still matter.

Review delivery, opens, clicks, bounces and complaints for a campaign. Privacy-related image fetches are filtered from the reported open rate, but neither an open nor a click proves a sale. Measure completed customer actions in your own application.

This page covers newsletters and scheduled broadcasts to saved audiences. Build event-triggered transactional sends with the Email API. The current campaign workflow does not establish a visual multistep journey builder or native A/B-test automation.

No. Use the dashboard editor or author HTML through the CLI and MCP workflows. React Email output can be stored as HTML with Bird placeholders preserved. The API, CLI and MCP operate on the same drafts and published versions you see in the dashboard.

Stored templates support Liquid and named parameters. Ordinary parameter names are flat, such as order_number. Reserved bird.contact fields read recipient properties. Broadcasts use registered contact properties and cannot use template loops; the messages API supports more general template sends.

Yes. Editing changes a draft. Publishing creates an immutable version used by later sends. Rolling back selects an earlier published version and resets the draft to that content; sends already accepted keep their content.

A template can hold language-specific subject, preview text and body content. Configure a default language and decide whether a missing language falls back or fails. Preview with representative contact values before publishing.

We generate the records for you: a DKIM TXT record to sign your mail, a return-path CNAME that aligns SPF (no apex SPF record required), and a DMARC TXT record. A tracking CNAME for branded open and click links is optional. Add the domain, paste the records at your DNS provider, and hit verify: most verifications resolve within minutes of DNS propagation, though it can occasionally take longer.

DMARC tells receiving servers what to do with mail that fails DKIM or SPF alignment, and where to send the aggregate reports that show who is sending as your domain. We require a DMARC record before a domain can send, and recommend starting at p=none, which monitors without affecting delivery. Once you have confirmed every legitimate source aligns, tighten the policy to p=quarantine or p=reject. If you already publish DMARC at your domain or a parent domain, we use it as is. Major inbox providers now expect bulk senders to publish a policy, so having one is increasingly part of reaching the inbox at volume.

Yes to both, and we recommend a dedicated subdomain, since it isolates your email reputation from your corporate mail. You can also run separate domains for transactional and marketing mail, or one per brand, each with its own authentication and reputation.

Consider a dedicated IP when you send consistent volume and need control over your own IP reputation. A low-volume or irregular sender may be better served by the shared pool. Bird warms a new dedicated IP automatically over roughly 30 days, with overflow routed through shared infrastructure during the ramp. Review your sending pattern with an email specialist before choosing.

Yes. Group IPs into pools and route each traffic type to its own pool. This separates the IPs carrying your campaign and transactional streams. Authentication, domain reputation and recipient engagement still matter for both.

Bird provides domain authentication, dedicated IP pools with managed warmup, recipient suppressions, preferences and sending metrics. Your team controls consent, content and sending behavior. Inbox Insights measures placement separately.

Use the stats API and dashboard to review bounce reasons, complaints, sending domains and mailbox-provider breakdowns. Inspect a specific recipient in the email log. Use Inbox Insights to investigate placement estimates and run campaign seed tests.

No. Healthy, Watching and Throttled classify sending risk. They do not change your sending rate or pause traffic. Investigate the affected campaign or list and decide whether to pause it.

Hard bounces create a suppression that blocks mail to the address. Complaints block non-transactional mail. Unsubscribes record a preference separately. Transactional delivery still depends on the address being valid and on any other blocking records.

Hard bounces create suppressions for all mail; complaints create suppressions for non-transactional mail. Manual suppressions block all categories. Soft bounces and deferrals do not create permanent recipient suppressions.

An unsubscribe records the recipient’s preference on the Preferences tab. It is separate from the suppression list. Both are checked when deciding whether to deliver, and deleting a contact does not erase its opt-out.

You can remove a suppression through the dashboard or API after investigating its cause. Removing one does not remove other blocking records or opt-out preferences. The suppressed@messagebird.dev sandbox address lets you test a rejected recipient without changing your list.

Use Email Lookup with an API key scoped for lookup. Submit one address and read its result, delivery confidence, risk flags and any typo suggestion. The dashboard, SDKs and CLI provide ways to try the same lookup.

The documented results are valid, neutral, risky, undeliverable and typo. Treat result as an open vocabulary and handle future values using delivery confidence. The valid boolean is the provider’s validity assessment; read it alongside the result and confidence, since it does not guarantee delivery.

Offer a typo suggestion for the person to confirm; never silently replace their address. Neutral means the mailbox could not be confirmed either way. Combine the result and confidence with your consent and sending policy.

No. A lookup helps assess address quality at that moment. It does not establish consent, remove opt-out preferences or guarantee inbox placement. Continue to honor suppression and preference records.

Use the batch API to assess up to 1,000 addresses in one request, within the 128 KiB request limit. Results follow submission order, including duplicates. Each answered entry is billed. Check the documented replay limits before retrying a batch; this page does not provide a list-upload control.

Review delivery, recorded opens and clicks, bounces, complaints and latency. Breakdowns cover sending domains, recipient domains, mailbox providers, tags, templates and broadcasts. Sending-IP breakdowns show delivery signals; engagement is not attributed to the IP that carried the message.

Stats aggregate the event stream with a short delay and return data_as_of. They use event time, so a click today can belong to a message sent earlier. Daily and hourly endpoints support the windows documented in the stats guide.

Delivery means acceptance by a receiving server. Use Inbox Insights for placement estimates and Competitive Insights for panel-observed competitor activity. For revenue or activation, connect campaign context to completed actions in your own application.

No. Create a Bird forwarding address and forward mail from an existing inbox. Use domain receiving when you want mail addressed directly to a subdomain you control.

Yes. Register and verify a dedicated subdomain, enable receiving and publish its provided MX records. Keep corporate email routing separate by using a receiving subdomain.

Subscribe to email.received webhooks or read messages through the inbound-messages API. Follow the webhook verification and retry guidance when processing events.

Inbound email parses messages arriving at forwarding addresses or receiving domains for your application to process. Agent Mailboxes provides an agent-owned inbox with message threads and a reply workflow.

Inbound email provides parsed messages, attachments and webhooks. An agent mailbox adds a durable address, conversation threads, receive rules and reply or compose operations, so an application can keep a conversation going.

Yes, with a receiving-enabled sending domain. You can also use a generated inbox.ai address or a custom handle when your plan allows one. An inbox.ai address remains reserved to your workspace after deletion; it is not reassigned to another customer.

Headers, extracted text and attachments follow the plan-supported retention tier. Original message bodies and received raw MIME have a 30-day window. A longer tier does not extend that original-content window or restore content already deleted.

Use mailbox webhooks to react to inbox messages. An SSE stream is also available for a live view, but it does not replay missed events after a disconnect. Use list endpoints to catch up; receive rules determine which arrivals generate inbox webhooks.

Inbox Insights is the current Bird dashboard product. Older Inbox Tracker product links lead here. For an existing eDataSource or legacy Tracker account, use that account’s documentation and support path; its features and access can differ.

Delivery rate records a receiving server accepting a message. Inbox Insights estimates inbox and spam placement from seeds and a measurement panel, alongside your Bird-measured delivery and engagement.

Use a workspace with access to Inbox Insights and a verified sending domain. Turn tracking on for the domain. Some domains or providers have no panel measurements yet; seed tests require an available pool and allowance.

No. Registration gives you seed addresses. Include them in your campaign before the send-by date. Results appear when those mailboxes receive the mail, and registration consumes the allowance even when no campaign is sent.

Review where that campaign landed at measured providers, its SPF, DKIM and DMARC results, and the engaged-versus-dormant split when the test used both cohorts.

Inbox Insights is a dashboard experience. Its internal endpoints are not a public API offering. Use the Email stats API for your own delivery and engagement reporting.

Yes. Competitive Insights is the current Bird dashboard experience for watching brands and comparing email programs. Older Competitive Tracker product links lead here. Existing legacy accounts can have a different feature set and access path.

No. The panel observes a sample of mailboxes and estimates the result. A watched brand uses its highest-volume sending domain, so activity on other domains is not included. Small or new senders may have no measurements.

The campaign feed includes captured subject lines and creative images when available. Some observed campaigns have no image. This experience does not provide a searchable copy of every competitor email or its complete customer journey.

Treat them as different measurements. Competitor read rate is estimated by the panel; Bird open tracking counts differently. The dashboard labels panel estimates and your own sending figures so you can interpret them correctly.

A brand profile shows its email service provider when the panel knows it. Missing provider information remains a gap rather than a guess.

Open Competitive Insights in a workspace with access, add brands by name or domain and review the watchlist. Your organization’s allowance determines how many brands you can watch. A demo can help you assess coverage before you plan around it.

Both are on-prem MTAs you run yourself instead of sending through our managed API. Momentum MTA is built around customizable workflows and routing for high-volume sending. PowerMTA is built to run on your own servers or any public cloud, such as AWS or Azure.

Teams with infrastructure or compliance requirements that call for running their own MTA, and teams that want independent visibility into inbox placement and competitive benchmarking rather than relying on their own send metrics alone. The first group runs Momentum MTA or PowerMTA. The second group uses Inbox Insights, which estimates inbox placement and supports campaign seed tests, or Competitive Insights, which benchmarks your program against other brands, and neither of those requires you to self-host anything.

SparkPost is part of Bird. Bird Email provides the sending, campaign and delivery workflows for new projects. An existing SparkPost integration is a separate integration: review its API calls, domain records and events with your account team before planning a move.

Bird Email has its own API and SDKs. Review the sending, templates, domain and webhook guides rather than assuming that a SparkPost request can be sent unchanged.

Momentum is our on-premises email infrastructure platform for high-volume sending, with customizable workflows, routing, and delivery parameters set through its Policy Manager. It is built to scale with your sending volume while keeping performance stable, and it supports full Unicode (SMTPUTF8) so you can send to international character sets.

Adaptive Delivery is Momentum's automatic traffic shaping. It watches how each mailbox provider responds to your mail and adjusts in real time: throttling, deferring, or briefly pausing a stream to protect your reputation, then ramping back up once things clear. You reach the inbox without manually babysitting send rates for every provider. The Intelligence Router shows you this happening across all your data sources, with real-time alerts whenever it makes an adjustment.

Yes to both. Momentum runs on your own servers, on any major cloud, or split across the two, so you can match it to your infrastructure, cost, and compliance needs and change that mix over time. It also keeps shipping: recent releases keep it current with modern operating systems, TLS 1.3, and up-to-date security and SMTP standards, and expose message events through real-time APIs you can feed into your own reporting and automation.

Yes. PowerMTA can relay some traffic to the hosted Bird Email API while delivering the rest straight from your own servers, which is the simplest way to try the hosted platform or migrate gradually without moving everything at once. PowerMTA itself runs on infrastructure you own, so those IPs stay yours to manage. Traffic you relay to the hosted platform can use our IPs there, or your own dedicated IPs, while everything else stays entirely under your control.

Virtual MTAs let you run several independent sending streams inside one PowerMTA instance, each with its own IPs, reputation, and limits. Use them to manage transactional mail, marketing mail or different customers separately. Shared domains and recipient-provider policies can still affect delivery across streams.

Yes. The API is HTTPS only. If you submit over SMTP instead, port 465 is encrypted from the first byte, and ports 587 and 2525 upgrade with STARTTLS: we refuse AUTH on those until the upgrade completes, so credentials never travel in the clear. Port 25 is not offered for submission at all. Use the regional endpoint that matches your API key. Official SDKs and the CLI read its region prefix and select that endpoint. Review the regions guide and your data-processing agreement for the storage and processing commitments that apply to your organization.

Only what you scope it to. A key carries a list of scopes such as emails, email_marketing, or domains, each at read or write, so a key that sends mail cannot manage your sending domains. Managing members, workspace settings, keys and IP pools requires a person’s permissions through the dashboard or an authorized CLI or MCP session. Each key also takes an allowlist of CIDR ranges, and requests from anywhere else are rejected.

Rotating issues the new key and leaves the old one working for a grace period, 24 hours by default, so you can roll it through your deploys. Pass zero to revoke the old key immediately instead. The old key keeps any earlier expiry. The replacement starts without an expiry, so set one explicitly if your application requires it.

Yes, over SAML 2.0 or OIDC, so Okta, Microsoft Entra ID and Google Workspace all work. It is set up per organization: your account team turns it on for you. Members who sign in with a password can turn on MFA themselves.

Yes. The audit log is a read-only, organization-wide record of every management action, with the actor, the workspace, the time and the outcome, and it exports to OCSF for your own SIEM. It covers configuration changes rather than the messages you send. Those live in the email log.

Certifications and security documentation live in the Trust Center at trust.bird.com. The data processing agreement, privacy statement and acceptable use policy are published at bird.com/legal, current versions alongside an archive of superseded ones. For a vendor questionnaire, your account team handles it.