Form.io vs Formstack (2026): which should you pick?

Pick Form.io if

• Fits if your developers need forms inside your own application and its data
• Makes sense if you must host data in your own infrastructure

Look elsewhere if

• Skip it if you want a free plan, because none exists
• Pricey if you only need a few forms: the lowest hosted plan is $300 a month
• Tight if you need several environments, since each needs its own server license
• Watch out: the hosted project may not collect personal or sensitive data
• Not for you if you want a no-code builder without developers

Pick Formstack if

• Fits if you want forms, generated documents and e-signatures from one vendor
• Works for Salesforce teams who want forms inside their org, or forms that pass through several reviewers

Look elsewhere if

• Pricey if you only need forms: $83 a month billed yearly ($99 monthly) for 1 builder, 25 forms and 1,000 submissions per form
• Not for you if you want a free plan, since there's only a 14-day trial
• Skip it if you need e-signatures or document generation on a budget, as those come with Suite at $250 a month
• Watch out: HIPAA compliance is an add-on, and API access, SSO and custom SLAs are on Enterprise with no public price
• Not for you if you want a phone or desktop app, as Formstack runs on the web only

Form.io

• There is no free plan; the hosted SaaS project is $300 a month after the 30-day trial, and the self-hosted options start higher.
• Self-hosted minimum is one project plus one API server environment, $660 a month; each extra environment needs its own server license.
• The SaaS project must not hold personal or sensitive data, per the pricing page, and lacks some security features.
• Add-ons per month: Reporting UI $660, accessibility $495, multi-tenancy $330, embedded builder $660. Five developer licenses are $2,640 a year.

Formstack

• There is no free plan; the entry price is $83 per month paid annually after a 14-day trial.
• The Forms plan includes one builder user, 25 forms and 1,000 submissions per form.
• Document generation and eSignatures come with the Suite plan, not the Forms plan.
• HIPAA compliance is listed as an add-on, and SSO and custom SLAs under Enterprise.

Form.io

JSON-driven forms

Forms are defined in JSON, rendered by the open-source formio.js library and stored through the platform's API.

Self-hosted containers

The platform ships as Docker containers that run in the customer's own environments and databases.

PDF forms

Optional PDF servers display PDF forms and export submissions to PDF.

Multi-tenancy and embedded builder

Paid add-ons support tenant-separated forms and data, and an embedded form builder inside your own application.

Security options

API Plus adds audit logging, field-level encryption and data separation for compliance needs.

Formstack

No-code form builder

Formstack Forms builds custom online forms without code and styles them with an organization's logos, colors and themes.

AI form creation

An AI-powered builder drafts a form, so users do not have to start from a blank page or add every field by hand.

Form prefill

Send prefilled links, or use SSO-powered prefill to populate information that is already known about the person completing the form.

Approvals and step logic

Group approvals, step logic and conditional routing move a submission through the people who need to review it.

Documents and Sign

The Suite plan generates documents from collected data, with 250 document deliveries a month, and includes unlimited eSignatures with no per-envelope fee.

Forms for Salesforce

A separate Salesforce-native product whose forms are built and managed inside a Salesforce org. It is sold with custom pricing.

Form.io

• SaaS Enterprise Project$300

  per month, hosted on portal.form.io

  One project with unlimited forms and developers, 1M submissions a month, 25 PDF-first forms and 1,000 PDF downloads. No PII; some security features missing.

• Enterprise Level Project$330

  per month per project; at least one required

  Unlimited forms, resources, developers, form builders and submissions, with a self-hosted developer portal.

• API Server$330

  per month per environment

  One server environment with unlimited API calls and submissions. An API Server or API Plus Server is required for each environment.

• API Plus Server$660

  per month per environment

  Adds audit logging, submission data separation, field-level encryption and container security scanning.

• PDF Server$330

  per month per environment

  Optional. Unlimited PDF submission downloads. The PDF Plus Server is $660 per month and adds uploads and a template designer.

Formstack

• Forms$83

  per month, paid annually ($99 billed monthly)

  1 builder user, 25 forms, 1,000 submissions per form and 2 GB of storage.

• Suite$250

  per month, paid annually ($299 billed monthly)

  Forms, Documents and Sign: 3 builder users, 100 forms, 5,000 submissions per form, 10 GB, 250 document deliveries a month and unlimited eSignatures.

• Salesforce SolutionsCustom

  Salesforce-native forms with document generation and eSignature, Experience Cloud integration and Salesforce Shield compatibility.

• EnterpriseCustom

  Unlimited users and submissions, SSO and advanced security, custom SLAs, API access and a dedicated Customer Success Manager.

Form.io

No public discounts listed.

Formstack

• Annual discount

  Save 2 months with annual plans

  Forms is $83 per month paid annually versus $99 on monthly billing, and Suite is $250 versus $299. The pricing page describes the saving as 2 months.

• Nonprofit

  25% nonprofit discount

  Formstack gives 25% off to 501(c)(3) organizations and comparable registered charities abroad. Educational and governmental institutions are not eligible.