curl --request PUT \
  --url https://api.sendkit.dev/templates/{id} \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/json' \
  --data '
{
  "sender_id": "550e8400-e29b-41d4-a716-446655440000",
  "subject": "Welcome to {{COMPANY}}",
  "name": "Updated Welcome Email",
  "folder_id": "3c90c3cc-0d44-4b50-8888-8dd25736052a",
  "html_content": "<h1>Welcome, {{FIRST_NAME}}!</h1>",
  "text_content": "Welcome, {{FIRST_NAME}}!",
  "reply_to": "support@yourdomain.com",
  "status": "published",
  "variables": [
    {
      "key": "FIRST_NAME",
      "type": "string",
      "fallback_value": "there"
    }
  ]
}
'

import requests

url = "https://api.sendkit.dev/templates/{id}"

payload = {
    "sender_id": "550e8400-e29b-41d4-a716-446655440000",
    "subject": "Welcome to {{COMPANY}}",
    "name": "Updated Welcome Email",
    "folder_id": "3c90c3cc-0d44-4b50-8888-8dd25736052a",
    "html_content": "<h1>Welcome, {{FIRST_NAME}}!</h1>",
    "text_content": "Welcome, {{FIRST_NAME}}!",
    "reply_to": "support@yourdomain.com",
    "status": "published",
    "variables": [
        {
            "key": "FIRST_NAME",
            "type": "string",
            "fallback_value": "there"
        }
    ]
}
headers = {
    "Authorization": "Bearer <token>",
    "Content-Type": "application/json"
}

response = requests.put(url, json=payload, headers=headers)

print(response.text)

const options = {
  method: 'PUT',
  headers: {Authorization: 'Bearer <token>', 'Content-Type': 'application/json'},
  body: JSON.stringify({
    sender_id: '550e8400-e29b-41d4-a716-446655440000',
    subject: 'Welcome to {{COMPANY}}',
    name: 'Updated Welcome Email',
    folder_id: '3c90c3cc-0d44-4b50-8888-8dd25736052a',
    html_content: '<h1>Welcome, {{FIRST_NAME}}!</h1>',
    text_content: 'Welcome, {{FIRST_NAME}}!',
    reply_to: 'support@yourdomain.com',
    status: 'published',
    variables: [{key: 'FIRST_NAME', type: 'string', fallback_value: 'there'}]
  })
};

fetch('https://api.sendkit.dev/templates/{id}', options)
  .then(res => res.json())
  .then(res => console.log(res))
  .catch(err => console.error(err));

<?php

$curl = curl_init();

curl_setopt_array($curl, [
  CURLOPT_URL => "https://api.sendkit.dev/templates/{id}",
  CURLOPT_RETURNTRANSFER => true,
  CURLOPT_ENCODING => "",
  CURLOPT_MAXREDIRS => 10,
  CURLOPT_TIMEOUT => 30,
  CURLOPT_HTTP_VERSION => CURL_HTTP_VERSION_1_1,
  CURLOPT_CUSTOMREQUEST => "PUT",
  CURLOPT_POSTFIELDS => json_encode([
    'sender_id' => '550e8400-e29b-41d4-a716-446655440000',
    'subject' => 'Welcome to {{COMPANY}}',
    'name' => 'Updated Welcome Email',
    'folder_id' => '3c90c3cc-0d44-4b50-8888-8dd25736052a',
    'html_content' => '<h1>Welcome, {{FIRST_NAME}}!</h1>',
    'text_content' => 'Welcome, {{FIRST_NAME}}!',
    'reply_to' => 'support@yourdomain.com',
    'status' => 'published',
    'variables' => [
        [
                'key' => 'FIRST_NAME',
                'type' => 'string',
                'fallback_value' => 'there'
        ]
    ]
  ]),
  CURLOPT_HTTPHEADER => [
    "Authorization: Bearer <token>",
    "Content-Type: application/json"
  ],
]);

$response = curl_exec($curl);
$err = curl_error($curl);

curl_close($curl);

if ($err) {
  echo "cURL Error #:" . $err;
} else {
  echo $response;
}

package main

import (
	"fmt"
	"strings"
	"net/http"
	"io"
)

func main() {

	url := "https://api.sendkit.dev/templates/{id}"

	payload := strings.NewReader("{\n  \"sender_id\": \"550e8400-e29b-41d4-a716-446655440000\",\n  \"subject\": \"Welcome to {{COMPANY}}\",\n  \"name\": \"Updated Welcome Email\",\n  \"folder_id\": \"3c90c3cc-0d44-4b50-8888-8dd25736052a\",\n  \"html_content\": \"<h1>Welcome, {{FIRST_NAME}}!</h1>\",\n  \"text_content\": \"Welcome, {{FIRST_NAME}}!\",\n  \"reply_to\": \"support@yourdomain.com\",\n  \"status\": \"published\",\n  \"variables\": [\n    {\n      \"key\": \"FIRST_NAME\",\n      \"type\": \"string\",\n      \"fallback_value\": \"there\"\n    }\n  ]\n}")

	req, _ := http.NewRequest("PUT", url, payload)

	req.Header.Add("Authorization", "Bearer <token>")
	req.Header.Add("Content-Type", "application/json")

	res, _ := http.DefaultClient.Do(req)

	defer res.Body.Close()
	body, _ := io.ReadAll(res.Body)

	fmt.Println(string(body))

}

HttpResponse<String> response = Unirest.put("https://api.sendkit.dev/templates/{id}")
  .header("Authorization", "Bearer <token>")
  .header("Content-Type", "application/json")
  .body("{\n  \"sender_id\": \"550e8400-e29b-41d4-a716-446655440000\",\n  \"subject\": \"Welcome to {{COMPANY}}\",\n  \"name\": \"Updated Welcome Email\",\n  \"folder_id\": \"3c90c3cc-0d44-4b50-8888-8dd25736052a\",\n  \"html_content\": \"<h1>Welcome, {{FIRST_NAME}}!</h1>\",\n  \"text_content\": \"Welcome, {{FIRST_NAME}}!\",\n  \"reply_to\": \"support@yourdomain.com\",\n  \"status\": \"published\",\n  \"variables\": [\n    {\n      \"key\": \"FIRST_NAME\",\n      \"type\": \"string\",\n      \"fallback_value\": \"there\"\n    }\n  ]\n}")
  .asString();

require 'uri'
require 'net/http'

url = URI("https://api.sendkit.dev/templates/{id}")

http = Net::HTTP.new(url.host, url.port)
http.use_ssl = true

request = Net::HTTP::Put.new(url)
request["Authorization"] = 'Bearer <token>'
request["Content-Type"] = 'application/json'
request.body = "{\n  \"sender_id\": \"550e8400-e29b-41d4-a716-446655440000\",\n  \"subject\": \"Welcome to {{COMPANY}}\",\n  \"name\": \"Updated Welcome Email\",\n  \"folder_id\": \"3c90c3cc-0d44-4b50-8888-8dd25736052a\",\n  \"html_content\": \"<h1>Welcome, {{FIRST_NAME}}!</h1>\",\n  \"text_content\": \"Welcome, {{FIRST_NAME}}!\",\n  \"reply_to\": \"support@yourdomain.com\",\n  \"status\": \"published\",\n  \"variables\": [\n    {\n      \"key\": \"FIRST_NAME\",\n      \"type\": \"string\",\n      \"fallback_value\": \"there\"\n    }\n  ]\n}"

response = http.request(request)
puts response.read_body

{
  "id": "550e8400-e29b-41d4-a716-446655440000",
  "folder_id": null,
  "name": "Welcome Email",
  "subject": "Welcome to {{COMPANY}}",
  "html_content": "<h1>Welcome, {{FIRST_NAME}}!</h1><p>Thanks for joining.</p>",
  "text_content": "Welcome, {{FIRST_NAME}}! Thanks for joining.",
  "reply_to": "support@yourdomain.com",
  "status": "published",
  "sender": {
    "id": "550e8400-e29b-41d4-a716-446655440000",
    "name": "John Doe",
    "username": "john",
    "email": "john@yourdomain.com",
    "reply_to": "reply@yourdomain.com",
    "created_at": "2026-03-03 10:00:00",
    "updated_at": "2026-03-03 10:00:00"
  },
  "variables": [
    {
      "key": "FIRST_NAME",
      "type": "string",
      "fallback_value": "there"
    }
  ],
  "created_at": "2026-03-03 10:00:00",
  "updated_at": "2026-03-03 10:00:00"
}

{
  "message": "Invalid API key."
}

{
  "message": "Not found."
}

{
  "message": "The email field is required."
}