> ## Documentation Index
> Fetch the complete documentation index at: https://docs.reallyquickemails.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Frequently Asked Questions

> Quick answers to the most common questions about the API.

## Sending emails

<AccordionGroup>
  <Accordion title="What's the difference between send-email, send-template-email, and send-batch?">
    | Endpoint                       | Best for                                                | Recipients   |
    | ------------------------------ | ------------------------------------------------------- | ------------ |
    | `POST /v1/send-email`          | Individual emails with direct HTML (transactional)      | 1            |
    | `POST /v1/send-template-email` | Individual emails using a saved template with variables | 1            |
    | `POST /v1/send-batch`          | Bulk sends to multiple recipients                       | Up to 10,000 |

    Quick rules:

    * `send-email` when you generate HTML from your system (confirmations, alerts).
    * `send-template-email` when you have templates in the visual editor and only send variables.
    * `send-batch` to send the same email (with personalized variables) to many recipients.
  </Accordion>

  <Accordion title="Can I send more than 10,000 emails?">
    Yes. You have two options:

    1. **Multiple calls to `/v1/send-batch`** — Split recipients into batches of up to 10,000 and make one call per batch.
    2. **Campaigns from the Dashboard** — Create a campaign with no limit. The system automatically processes in batches with built-in rate limiting. Ideal for 50k+ emails.
  </Accordion>

  <Accordion title="What are the sending limits?">
    | Limit                                             | Value                     |
    | ------------------------------------------------- | ------------------------- |
    | Recipients per batch request                      | 10,000                    |
    | Recipients per individual send (`/v1/send-email`) | 50                        |
    | Attachments                                       | 10 per email, 10 MB total |

    Daily and monthly limits also apply depending on your account. When you reach them, sends are queued and resume on their own. Contact support if you need more capacity.
  </Accordion>

  <Accordion title="Can I schedule a send for later?">
    Yes. Use the `scheduled_at` field with ISO 8601:

    ```json theme={null}
    { "scheduled_at": "2026-04-01T10:00:00Z" }
    ```

    It works in `/send-email` (accepts ISO 8601, natural language like `"tomorrow at 3pm"`, and the `timezone` field) and in `/v1/send-batch` (ISO 8601 only). See [Scheduling Sends](/en/guides/scheduling).
  </Accordion>

  <Accordion title="What happens if I send an email to someone who unsubscribed?">
    The email is skipped automatically. The behavior depends on the endpoint:

    * **`/v1/send-template-email`**: the suppression is detected at request time — it responds `200` with `"skipped": true` and `suppression_reason` (see [v1 API](/en/api-reference/public-api)).
    * **`/v1/send-email` and `/send-email`**: the suppression is detected at request time — it responds `200` with `"suppressed": true` and `reason: "recipient_suppressed"`, without queuing anything (see [Suppressed recipient](/en/api-reference/send-email#suppressed-recipient)).
    * **`/v1/send-batch`**: the API responds `200` and applies the suppression in the background. The email is never sent; the activity ends up with `current_status: "suppressed"`, which can be queried via the [Activity API](/en/api-reference/activity).

    In all API send cases, the [`email.suppressed`](/en/api-reference/webhooks#emailsuppressed) webhook is also emitted so you can sync your side.

    The suppression list includes recipients by:

    * **Unsubscribe** — click on an unsubscribe link
    * **Hard bounce** — permanent bounce
    * **Complaint** — marked as spam
  </Accordion>

  <Accordion title="How do I track whether an email was delivered?">
    Each send returns an `activity_id` (or `email_id`). Delivery events update the status:

    ```
    queued → sent → delivered (success)
    queued → sent → bounced (bounce)
    queued → sent → complained (spam)
    ```

    Status is visible in Dashboard → Activity, or queryable via the [Activity API](/en/api-reference/activity). For `send-batch`, there's one `activity_id` per recipient.
  </Accordion>
</AccordionGroup>

## Domains and deliverability

<AccordionGroup>
  <Accordion title="Why do my emails land in spam?">
    Most common causes:

    1. **Unverified domain** — DKIM, SPF, DMARC. Verify with `POST /domains/:domain/verify`.
    2. **Cold domain** — needs gradual warming: **150 emails on day 1**, 250 on day 2, 400 on day 3, up to around 2,000 by day 7. Ramping all at once burns the domain.
    3. **High bounce or complaint rate** — clean your list. Above 4% bounces you should pause; above 0.1% complaints reputation drops fast.
    4. **Links that don't match your domain** — if the `From` is yours but links point elsewhere, filters read it as phishing. Fixed with a [tracking domain](/en/concepts/tracking).
    5. **Suspicious content** — too many links, all caps, words like "FREE"/"OFFER"/"URGENT", images without alt text.
    6. **No unsubscribe link** — ReallyQuickEmails adds `List-Unsubscribe` automatically, but include a visible link.

    <Warning>
      If everything shows as verified and you still land in spam, the problem is **reputation**, not configuration. See [Deliverability and authentication](/en/concepts/deliverability).

      And don't use an email you send to yourself within your own domain as a test: Google penalizes it for resembling spoofing, even when everything is set up correctly.
    </Warning>
  </Accordion>

  <Accordion title="How do I verify my domain?">
    1. Register the domain with `POST /domains/register`
    2. Configure the 8 DNS records at your provider:
       * 1 TXT domain verification
       * 3 CNAME DKIM
       * 1 TXT SPF
       * 1 TXT DMARC
       * 1 MX `send` (Return-Path)
       * 1 TXT `send` (Return-Path)
    3. Wait 5–10 min for propagation
    4. Verify with `POST /domains/:domain/verify`
    5. When `can_send: true`, you're set

    Full guide in [Domains](/en/api-reference/domains).
  </Accordion>

  <Accordion title="How long does DNS verification take?">
    | Provider       | Typical time |
    | -------------- | ------------ |
    | Cloudflare     | 1–5 min      |
    | GoDaddy        | 5–30 min     |
    | Namecheap      | 5–30 min     |
    | Route 53 (AWS) | 1–5 min      |
    | Others         | up to 48 h   |
  </Accordion>
</AccordionGroup>

## Templates

<AccordionGroup>
  <Accordion title="What syntax do variables use?">
    | Syntax       | Example    |
    | ------------ | ---------- |
    | Double brace | `{{name}}` |
    | Single brace | `{name}`   |

    Also:

    * **Fallback** — `{name || "Customer"}`
    * **Raw HTML** — `{!htmlContent}`
    * **Loops** — `{{#each products}}...{{/each}}`
    * **Conditionals** — `{{#if premium}}...{{/if}}`

    See [Templates and Variables](/en/guides/templates).
  </Accordion>

  <Accordion title="What formatting helpers are available?">
    | Helper              | Use                 | Example                                                       |
    | ------------------- | ------------------- | ------------------------------------------------------------- |
    | `formatCurrency`    | Currency            | `{{formatCurrency total}}` → `$61,970.00`                     |
    | `multiply`          | Multiplication      | `{{multiply quantity price}}`                                 |
    | `formatDate`        | Human-readable date | `{{formatDate date}}` → `15/3/2026`                           |
    | `formatDate "long"` | Long format         | `{{formatDate date "long"}}` → `domingo, 15 de marzo de 2026` |
    | `default`           | Default             | `{{default name "Customer"}}`                                 |
    | `json`              | Serializes to JSON  | `{{json data}}`                                               |
  </Accordion>

  <Accordion title="Can I use the same template for send-email and send-batch?">
    Yes. Templates created in the visual editor work in:

    * `POST /v1/send-template-email` (individual, `template_id` + `variables`)
    * `POST /v1/send-batch` (bulk, `templateId` + `data` per recipient)
    * Campaigns from the Dashboard
  </Accordion>
</AccordionGroup>

## Campaigns

<AccordionGroup>
  <Accordion title="Difference between send-batch and a campaign?">
    | Aspect    | send-batch (API)            | Campaign (Dashboard)             |
    | --------- | --------------------------- | -------------------------------- |
    | Limit     | 10,000 per request          | No limit                         |
    | Creation  | Code (curl, SDK)            | Visual 5-step wizard             |
    | Template  | Direct HTML or templateId   | Visual campaign editor           |
    | Variables | `data` per recipient        | CSV upload, mapping, defaults    |
    | Batches   | Manual                      | Automatic                        |
    | Warming   | Manual                      | Configurable batch mode          |
    | Retries   | No                          | Automatic                        |
    | Stats     | Via individual activity\_id | Dashboard with aggregate metrics |

    Rule: `send-batch` for programmatic integrations. Campaigns for large sends from the UI.
  </Accordion>

  <Accordion title="Can I pause a campaign in progress?">
    Yes. From the Dashboard you can pause a campaign in `processing`. Emails already queued keep sending, but no new batches are dispatched. Resume from the Dashboard.
  </Accordion>

  <Accordion title="What happens if my campaign gets stuck in 'rate_limited'?">
    Your account's sending limit was reached. It resumes automatically when the limit resets. You can also resume it manually from the Dashboard.
  </Accordion>
</AccordionGroup>

## API and authentication

<AccordionGroup>
  <Accordion title="Where do I find my API keys?">
    1. Dashboard → your project → **Settings → Integrations → API Keys**
    2. Copy the corresponding key:
       * **Live** (`sk_live_*` or `sk_proj_*`) → production traffic
       * **Test** (`sk_test_*`) → development, doesn't consume quota

    See [API Keys](/en/guides/api-keys) for details.
  </Accordion>

  <Accordion title="Why am I getting a 401 error?">
    | Cause                          | Solution                                    |
    | ------------------------------ | ------------------------------------------- |
    | Missing `Authorization` header | Add `Authorization: Bearer sk_live_...`     |
    | Incorrect format               | Check the space after `Bearer`              |
    | Unrecognized prefix            | Only `sk_proj_*`, `sk_live_*`, `sk_test_*`  |
    | Invalid or revoked key         | Generate a new one from Settings → API Keys |
  </Accordion>

  <Accordion title="Does the API have rate limiting?">
    The endpoints don't have their own rate limiting; the limit is imposed by your account's sending capacity. When you reach it, emails are queued and sent on their own once capacity is available.
  </Accordion>

  <Accordion title="How do I avoid double sends on retries?">
    Pass an `Idempotency-Key: <unique-string>` header (1–256 characters) in `/send-email` or `/v1/send-batch`. A retry with the same key within 24h returns the cached response with `Idempotency-Replayed: true`. See [API Keys](/en/guides/api-keys#idempotency).
  </Accordion>
</AccordionGroup>

## Support

<Info>
  Contact us at [harold@dropout.cl](mailto:harold@dropout.cl), including: Project ID, endpoint used, request body, error/response, and approximate timestamp.
</Info>