---
title: "Schedule API with Natural Language"
slug: schedule-api-with-natural-language
description: "Use natural language to schedule emails programmatically."
created_at: "2024-10-03"
updated_at: "2025-02-11"
image: https://cdn.resend.com/posts/schedule-api-with-natural-language.jpg
humans: ["bu-kinoshita"]
featured: true
---

A couple of weeks ago, we introduced the ability to [schedule emails programmatically](/blog/introducing-the-schedule-email-api).

After seeing the positive feedback, we decided to take it a step further and introduce the ability to schedule emails using natural language.

## Before

When we first launched, you could schedule an email by providing a timestamp in [ISO 8601](https://en.wikipedia.org/wiki/ISO_8601) format (e.g: `2024-08-05T11:52:01.858Z`).

This is still supported, since it provides flexibility for date and time manipulation.

<CodeTabs codeHeight={300}>
```nodejs
import { Resend } from 'resend';

const resend = new Resend('re_xxxxxxxxx');

const oneMinuteFromNow = new Date(Date.now() + 1000 * 60).toISOString();

await resend.emails.send({
  from: 'Acme <onboarding@resend.dev>',
  to: ['delivered@resend.dev'],
  subject: 'hello world',
  html: '<p>it works!</p>',
  scheduledAt: oneMinuteFromNow,
});
```

```ruby
require "resend"

Resend.api_key = "re_xxxxxxxxx"

one_minute_from_now = (Time.now + 1 * 60).strftime("%Y-%m-%dT%H:%M:%S.%L%z")

params = {
  "from": "Acme <onboarding@resend.dev>",
  "to": ["delivered@resend.dev"],
  "subject": "hello world",
  "html": "<p>it works!</p>",
  "scheduled_at": one_minute_from_now
}

Resend::Emails.send(params)
```

```php
$resend = Resend::client('re_xxxxxxxxx');

$oneMinuteFromNow = (new DateTime())->modify('+1 minute')->format(DateTime::ISO8601);

$resend->emails->send([
  'from' => 'Acme <onboarding@resend.dev>',
  'to' => ['delivered@resend.dev'],
  'subject' => 'hello world',
  'html' => '<p>it works!</p>',
  'scheduled_at' => $oneMinuteFromNow
]);
```

```python
import resend
from datetime import datetime, timedelta

resend.api_key = "re_xxxxxxxxx"

one_minute_from_now = (datetime.now() + timedelta(minutes=1)).isoformat()

params: resend.Emails.SendParams = {
  "from": "Acme <onboarding@resend.dev>",
  "to": ["delivered@resend.dev"],
  "subject": "hello world",
  "html": "<p>it works!</p>",
  "scheduled_at": one_minute_from_now
}

resend.Emails.send(params)
```

```go
import (
	"fmt"

	"github.com/resend/resend-go/v2"
)

func main() {
  ctx := context.TODO()
  client := resend.NewClient("re_xxxxxxxxx")

  oneMinuteFromNow := time.Now().Add(time.Minute * time.Duration(1))
  oneMinuteFromNowISO := oneMinuteFromNow.Format("2006-01-02T15:04:05-0700")

  params := &resend.SendEmailRequest{
    From:        "Acme <onboarding@resend.dev>",
    To:          []string{"delivered@resend.dev"},
    Subject:     "hello world",
    Html:        "<p>it works!</p>",
    ScheduledAt: oneMinuteFromNowISO
  }

  sent, err := client.Emails.SendWithContext(ctx, params)

  if err != nil {
    panic(err)
  }
  fmt.Println(sent.Id)
}
```

```rust
use chrono::{Local, TimeDelta};
use resend_rs::types::CreateEmailBaseOptions;
use resend_rs::{Resend, Result};

#[tokio::main]
async fn main() -> Result<()> {
  let resend = Resend::new("re_xxxxxxxxx");

  let from = "Acme <onboarding@resend.dev>";
  let to = ["delivered@resend.dev"];
  let subject = "hello world";
  let one_minute_from_now = Local::now()
    .checked_add_signed(TimeDelta::minutes(1))
    .unwrap()
    .to_rfc3339();

  let email = CreateEmailBaseOptions::new(from, to, subject)
    .with_html("<p>it works!</p>")
    .with_scheduled_at(&one_minute_from_now);

  let _email = resend.emails.send(email).await?;

  Ok(())
}
```

```java
import com.resend.*;

public class Main {
    public static void main(String[] args) {
        Resend resend = new Resend("re_xxxxxxxxx");

        String oneMinuteFromNow = Instant
          .now()
          .plus(1, ChronoUnit.MINUTES)
          .toString();

        CreateEmailOptions params = CreateEmailOptions.builder()
                .from("Acme <onboarding@resend.dev>")
                .to("delivered@resend.dev")
                .subject("hello world")
                .html("<p>it works!</p>")
                .scheduledAt(oneMinuteFromNow)
                .build();

        CreateEmailResponse data = resend.emails().send(params);
    }
}
```

```dotnet
using Resend;

IResend resend = ResendClient.Create( "re_xxxxxxxxx" );

var resp = await resend.EmailSendAsync( new EmailMessage()
{
    From = "Acme <onboarding@resend.dev>",
    To = "delivered@resend.dev",
    Subject = "hello world",
    HtmlBody = "<p>it works!</p>",
    MomentSchedule = DateTime.UtcNow.AddMinutes( 1 ),
} );
Console.WriteLine( "Email Id={0}", resp.Content );
```

```curl
curl -X POST 'https://api.resend.com/emails' \
 -H 'Authorization: Bearer re_xxxxxxxxx' \
 -H 'Content-Type: application/json' \
 -d $'{
  "from": "Acme <onboarding@resend.dev>",
  "to": ["delivered@resend.dev"],
  "subject": "hello world",
  "html": "<p>it works!</p>",
  "scheduled_at": "2024-08-20T11:52:01.858Z"
}'
```
</CodeTabs>

## Now

Starting today, you can also use natural language to schedule an email.

The date can be defined in a more flexible format, such as `"in 1 hour"`, `"tomorrow at 9am"`, or `"Friday at 3pm ET"`.

<CodeTabs>
```nodejs
import { Resend } from 'resend';

const resend = new Resend('re_xxxxxxxxx');

await resend.emails.send({
  from: 'Acme <onboarding@resend.dev>',
  to: ['delivered@resend.dev'],
  subject: 'hello world',
  html: '<p>it works!</p>',
  scheduledAt: 'in 1 min',
});
```

```php
$resend = Resend::client('re_xxxxxxxxx');

$resend->emails->send([
  'from' => 'Acme <onboarding@resend.dev>',
  'to' => ['delivered@resend.dev'],
  'subject' => 'hello world',
  'html' => '<p>it works!</p>',
  'scheduled_at' => 'in 1 min'
]);
```

```python
import resend
resend.api_key = "re_xxxxxxxxx"

params: resend.Emails.SendParams = {
  "from": "Acme <onboarding@resend.dev>",
  "to": ["delivered@resend.dev"],
  "subject": "hello world",
  "html": "<p>it works!</p>",
  "scheduled_at": "in 1 min"
}

resend.Emails.send(params)
```

```ruby
require "resend"

Resend.api_key = "re_xxxxxxxxx"

params = {
  "from": "Acme <onboarding@resend.dev>",
  "to": ["delivered@resend.dev"],
  "subject": "hello world",
  "html": "<p>it works!</p>",
  "scheduled_at": "in 1 min"
}

Resend::Emails.send(params)
```

```go
import (
	"fmt"

	"github.com/resend/resend-go/v2"
)

func main() {
  ctx := context.TODO()
  client := resend.NewClient("re_xxxxxxxxx")

  params := &resend.SendEmailRequest{
    From:        "Acme <onboarding@resend.dev>",
    To:          []string{"delivered@resend.dev"},
    Subject:     "hello world",
    Html:        "<p>it works!</p>",
    ScheduledAt: "in 1 min"
  }

  sent, err := client.Emails.SendWithContext(ctx, params)

  if err != nil {
    panic(err)
  }
  fmt.Println(sent.Id)
}
```

```rust
use resend_rs::types::CreateEmailBaseOptions;
use resend_rs::{Resend, Result};

#[tokio::main]
async fn main() -> Result<()> {
  let resend = Resend::new("re_xxxxxxxxx");

  let from = "Acme <onboarding@resend.dev>";
  let to = ["delivered@resend.dev"];
  let subject = "hello world";

  let email = CreateEmailBaseOptions::new(from, to, subject)
    .with_html("<p>it works!</p>")
    .with_scheduled_at("in 1 min");

  let _email = resend.emails.send(email).await?;

  Ok(())
}
```

```java
import com.resend.*;

public class Main {
    public static void main(String[] args) {
        Resend resend = new Resend("re_xxxxxxxxx");

        CreateEmailOptions params = CreateEmailOptions.builder()
                .from("Acme <onboarding@resend.dev>")
                .to("delivered@resend.dev")
                .subject("hello world")
                .html("<p>it works!</p>")
                .scheduledAt("in 1 min")
                .build();

        CreateEmailResponse data = resend.emails().send(params);
    }
}
```

```dotnet
using Resend;

IResend resend = ResendClient.Create( "re_xxxxxxxxx" );

var resp = await resend.EmailSendAsync( new EmailMessage()
{
    From = "Acme <onboarding@resend.dev>",
    To = "delivered@resend.dev",
    Subject = "hello world",
    HtmlBody = "<p>it works!</p>",
    MomentSchedule = "in 1 min",
} );
Console.WriteLine( "Email Id={0}", resp.Content );
```

```curl
curl -X POST 'https://api.resend.com/emails' \
 -H 'Authorization: Bearer re_xxxxxxxxx' \
 -H 'Content-Type: application/json' \
 -d $'{
  "from": "Acme <onboarding@resend.dev>",
  "to": ["delivered@resend.dev"],
  "subject": "hello world",
  "html": "<p>it works!</p>",
  "scheduled_at": "in 1 min"
}'
```
</CodeTabs>

As a reminder, emails can be scheduled up to 72 hours in advance.

## Conclusion

We hope this new feature improves the developer experience and makes it easier for you to schedule emails without the need to write more code or calculate timestamps using external libraries.