Svelte file upload form
Build a file upload form in Svelte with no backend and no upload API. The component posts multipart FormData straight to Formpaste, so the file lands in your inbox with the other fields. Copy the code and add your access key.
How to build it
- Create a form in your Formpaste dashboard and copy its access key.
- Connect Storage in the dashboard so the form can accept uploads.
- Copy the Svelte component above, add your access key, then deploy.
Prompt for your AI coding agent
Add a Formpaste file upload form to my Svelte app. Use a single-file component with a file input that POSTs the raw FormData (multipart/form-data, not URLSearchParams) to https://api.formpaste.com/submit with a hidden access_key input. Do not build an upload endpoint of my own.Or connect the Formpaste MCP server to Claude Code, Codex, Cursor, Claude Desktop, VS Code, or any mcp-remote client. See the setup guide.
Svelte gotchas
A Svelte contact form is a single-file component with bind:value on the fields and an on:submit|preventDefault handler that posts to Formpaste. There is no backend and no API of your own. Put the fetch in the component and you are done.
It is a single-file component
The form lives in a .svelte component with a <script> block. Bind the fields with bind:value or read a FormData off the form element on submit, then post to the Formpaste endpoint. No store or library is required for a simple form.
No API of your own
You do not proxy through your own server. The component posts straight to the Formpaste endpoint, which removes a mailer and a submissions store you would otherwise build.
Handle the response with a reactive status
The endpoint returns JSON (success, message, id). Await the fetch and set a reactive status variable to show your own success or error state, or set a redirect URL in the dashboard and skip the client handling.
Svelte 4 or Svelte 5, both work
The examples use a <script> block with a plain status variable, which works in every Svelte version. On Svelte 5 you can use runes like $state instead, but the same fetch and the same POST are all Formpaste needs.
What to get right
A file means multipart, not urlencoded
As soon as the form has a file input, it must post multipart form data. The generated code sets enctype and sends the raw FormData, so the file rides along with the other fields. No upload endpoint of your own is needed.
The upload is client to Formpaste, direct
The browser posts the file straight to Formpaste, so your app never buffers or parses the upload. That sidesteps serverless body-size and runtime limits entirely.
Set expectations on size and type
Tell people what you accept. File uploads are a Pro feature; connect Storage in the dashboard first, and keep the input honest about accepted types and size.
How it works
Three simple steps for form submissions to land in your email inbox.
Create your form, set your form's action URL to Formpaste's endpoint, and add your access key.
Create your form
Sign up, verify your email, and create an access key in your dashboard.
Copy the code
Paste the snippet above into your project. Pick CSS or Tailwind to match your site.
<script lang="ts">
let status: "idle" | "sending" | "ok" | "error" = "idle";
async function onSubmit(e: SubmitEvent) {
status = "sending";
const form = new FormData(e.target as HTMLFormElement);
const res = await fetch("https://api.formpaste.com/submit", { method: "POST", body: form });
status = res.ok ? "ok" : "error";
}
</script>
{#if status === "ok"}
<p>Thanks - your message was sent.</p>
{:else}
<form on:submit|preventDefault={onSubmit} class="mx-auto flex w-full max-w-md flex-col gap-4 rounded-xl border border-gray-200 bg-white p-6 shadow-sm dark:border-gray-800 dark:bg-gray-950">
<input type="hidden" name="access_key" value="YOUR_ACCESS_KEY_HERE">
<label class="flex flex-col gap-1.5 text-sm font-medium text-gray-900 dark:text-gray-100">Name
<input type="text" name="name" required class="rounded-md border border-gray-300 bg-white px-3 py-2 text-sm text-gray-900 shadow-sm outline-none focus-visible:ring-2 focus-visible:ring-gray-900 dark:border-gray-700 dark:bg-gray-900 dark:text-gray-100 dark:focus-visible:ring-gray-100" />
</label>
<label class="flex flex-col gap-1.5 text-sm font-medium text-gray-900 dark:text-gray-100">Email
<input type="email" name="email" placeholder="you@example.com" required class="rounded-md border border-gray-300 bg-white px-3 py-2 text-sm text-gray-900 shadow-sm outline-none focus-visible:ring-2 focus-visible:ring-gray-900 dark:border-gray-700 dark:bg-gray-900 dark:text-gray-100 dark:focus-visible:ring-gray-100" />
</label>
<label class="flex flex-col gap-1.5 text-sm font-medium text-gray-900 dark:text-gray-100">File
<input type="file" name="file" required class="rounded-md border border-gray-300 bg-white px-3 py-2 text-sm text-gray-900 shadow-sm outline-none focus-visible:ring-2 focus-visible:ring-gray-900 dark:border-gray-700 dark:bg-gray-900 dark:text-gray-100 dark:focus-visible:ring-gray-100" />
</label>
<label class="flex flex-col gap-1.5 text-sm font-medium text-gray-900 dark:text-gray-100">Message
<textarea name="message" class="min-h-28 rounded-md border border-gray-300 bg-white px-3 py-2 text-sm text-gray-900 shadow-sm outline-none focus-visible:ring-2 focus-visible:ring-gray-900 dark:border-gray-700 dark:bg-gray-900 dark:text-gray-100 dark:focus-visible:ring-gray-100"></textarea>
</label>
<button type="submit" class="w-full rounded-md bg-gray-900 px-4 py-2 text-sm font-medium text-white shadow-sm transition-colors hover:bg-gray-800 disabled:opacity-60 dark:bg-white dark:text-gray-900 dark:hover:bg-gray-200" disabled={status === "sending"}>Upload</button>
{#if status === "error"}<p>Something went wrong. Please try again.</p>{/if}
</form>
{/if}Add your access key
Replace the placeholder with your access key to start receiving submissions.
<input type="hidden" name="access_key" value="YOUR_ACCESS_KEY_HERE">Svelte file upload form FAQ
Paste a form. Get submissions.
Instantly without setting up any backend, servers or databases. 250 submissions/mo free - no credit card.