Can I add a file upload field to any form?

Yes. A file upload field can be added to any form, alongside your other questions. Use it to collect documents, images, CVs, briefs, or portfolios.

Where are uploaded files stored?

Uploaded files are stored in a private Supabase Storage bucket. It is not publicly listable, so files cannot be browsed or discovered by outsiders.

Are uploaded files publicly accessible?

No. The storage bucket is private and never publicly listable. Files are not exposed on a public URL just because they were uploaded through a form.

How are large files handled?

Respondents upload directly to storage using short-lived signed URLs, so large files do not pass through a fragile server relay and are less likely to fail on the way up.

Can a respondent skip a required file upload?

No. Formius validates answers and uploads on the server when the form is submitted, so client-side rules such as a required file or limits cannot be bypassed.

How do I get the files people upload?

You download submitted files directly from the responses view, in the same place you read the answers, so there is no separate file-sharing tool to manage.

File collection

File upload forms

Add a file upload field to any form and collect real documents alongside the answers, securely.

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Plenty of things you need to collect are not text. A job application needs a CV, a design brief needs reference files, a grant form needs supporting documents, a contest needs a portfolio. Formius lets you add a file upload field to any form, so respondents attach real files in the same step where they answer your questions.

You do not need a separate file-sharing tool or a shared inbox on the side. The document arrives attached to the response it belongs to, stored privately, so everything you collected stays in one place and one flow.

Add an upload field to any form

A file upload field works like any other field on your form. Drop it in wherever you need it, and respondents get a place to attach a document, an image, a CV, a brief, or a portfolio right next to the rest of their answers.

Because it is a normal field, you can require it when the file is essential and leave it optional when it is a nice-to-have, and it sits inside the same form you already designed.

Uploads go straight to private storage

Files are stored in a private storage bucket, not on a public URL and never in a publicly listable folder. Nobody can browse or guess their way to what your respondents sent.

To keep large files reliable, respondents upload directly to storage using short-lived signed URLs that Formius issues for each upload. The file does not have to squeeze through a fragile server relay, so a big attachment is far less likely to time out or fail partway.

Stored in a private Supabase Storage bucket that is never publicly listable.
Uploaded directly to storage through short-lived signed URLs, so large files do not depend on a server relay.
Each file stays attached to the response it came in with, not scattered across a separate tool.

Rules are enforced on the server, not just the browser

Client-side checks are convenient, but they can be bypassed. Formius validates both the answers and the uploads again on the server when a form is submitted, so a respondent cannot skip a required file or slip past your limits by editing the page. The rules you set are the rules that actually apply.

Download submitted files from the responses view

When you review a submission, its files are right there. You download the documents a respondent sent straight from the responses view, in the same place you read their answers, so collecting and retrieving files is one continuous workflow instead of two disconnected tools.

Frequently asked questions

Can I add a file upload field to any form?: Yes. A file upload field can be added to any form, alongside your other questions. Use it to collect documents, images, CVs, briefs, or portfolios.
Where are uploaded files stored?: Uploaded files are stored in a private Supabase Storage bucket. It is not publicly listable, so files cannot be browsed or discovered by outsiders.
Are uploaded files publicly accessible?: No. The storage bucket is private and never publicly listable. Files are not exposed on a public URL just because they were uploaded through a form.
How are large files handled?: Respondents upload directly to storage using short-lived signed URLs, so large files do not pass through a fragile server relay and are less likely to fail on the way up.
Can a respondent skip a required file upload?: No. Formius validates answers and uploads on the server when the form is submitted, so client-side rules such as a required file or limits cannot be bypassed.
How do I get the files people upload?: You download submitted files directly from the responses view, in the same place you read the answers, so there is no separate file-sharing tool to manage.

Related features

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