Three open source tools can take over from Typeform or Google Forms on your own server, and each was built for a different job. LimeSurvey is research survey software: long questionnaires with branching, panels invited by email, exports to R, SPSS and Stata. It runs on a plain PHP server with an SQL database, under the GPL, with no proprietary directory in its code. Formbricks pops surveys up inside an app or on a website when someone clicks or views a page, and needs seven services and at least 4 GB of RAM. OpnForm builds web forms the Typeform way and imports the ones you already made in Typeform or Google Forms, but its free self-hosted edition stops at two accounts per instance.
Research survey, web form or in-app survey
LimeSurvey builds surveys from more than 30 question types in over 80 languages. Its logic is written in ExpressionScript, which has more than 80 functions: a question only shows when its relevance equation is true, and a computed value can be stored with the response. A participant table gives each person an access code, sends invitations and reminders, and is filled from a CSV file or an LDAP directory. The repository describes LimeSurvey as a free alternative to SurveyMonkey, Typeform, Qualtrics and Google Forms.
Formbricks starts from the in-app survey. Its SDK, for the web, iOS and Android, opens a survey when the user does something: a page view, a click, the pointer leaving the window, scrolling halfway down, time spent on a page, or an event your code sends with formbricks.track(). Formbricks also runs link surveys and surveys embedded in an email. Its README calls it "the open source Qualtrics alternative", and version 5 added a feedback directory plus NPS, CSAT and CES dashboards, all on the paid list.
OpnForm is a general-purpose web form builder. On the page comparing it with Formbricks, the vendor aims it at lead capture, registrations and job applications. Its Focused mode shows one question at a time, as Typeform does, and version 2 imports forms from Typeform, Tally, Google Forms and Fillout. Responses can also fill in a PDF template, and an MCP server lets an AI assistant create and manage forms and read responses, with read-only access.
What each tool needs to run
Read from the repositories and documentation on 7 October 2026.
| Tool | Licence | What you run | Collects through | Free edition limits | Latest release |
|---|---|---|---|---|---|
| LimeSurvey | GPL-2.0 or later | PHP 8.1.29 or later, Apache or nginx, MySQL, MariaDB, PostgreSQL or SQL Server; no official Docker image | public link or email invitation | none, but one-click updates are paid | 7.4.0, 28 Sep 2026 on GitHub; 7.5.0 on the download page |
| Formbricks | AGPL-3.0, except apps/web/modules/ee; SDKs under MIT | seven services, including PostgreSQL 18, Valkey, SpiceDB and Cube; 4 GB of RAM minimum, 8 GB for light load | in-app, link, email | one workspace; no SSO, no two-factor login, no respondent identification | 6.0.2, 1 Oct 2026 |
| OpnForm | AGPL-3.0 or later, except api/app/Enterprise/ | seven containers, including PostgreSQL 16, Redis 7 and Nginx; RAM not documented | web form, standalone or embedded in a page | two accounts per instance; OpnForm branding stays | 2.5.0, 2 Sep 2026 |
LimeSurvey has the fewest moving parts: a PHP web server and an SQL database. Its manual asks for 250 MB of disk, gives no memory figure and doesn't cover Docker. The vendor publishes no image, a request to document Docker installs has been open since March 2024, and the community image martialblog/docker-limesurvey already tracks 7.4.0. Formbricks asks for far more. Its production Compose file starts the app, PostgreSQL with pgvector, Valkey, SpiceDB, Cube, and the Formbricks Hub API and worker. Cube and Hub have been required since version 5 and SpiceDB since version 6, and protected operations are refused when SpiceDB is down. Its docs call 4 GB of RAM a floor. OpnForm's Compose file also runs seven containers, with a Laravel API, a queue worker, a scheduler and a Nuxt client around PostgreSQL, Redis and Nginx, but its docs give no minimum memory.
Where responses are stored, and what it means for GDPR
Responses on a self-hosted instance stay in its own database: whichever SQL database you picked for LimeSurvey, PostgreSQL for Formbricks and OpnForm. The third-party services you plug in are a separate question. OpnForm's captcha goes through hCaptcha or reCAPTCHA, and Formbricks' spam protection through reCAPTCHA v3, in its paid edition only, while LimeSurvey generates its own captcha. An OpnForm instance with an Enterprise licence also sends its key, an instance ID and usage metadata to api.opnform.com, and only keeps its licensed features for a short grace period if that API stops answering. That matters for an air-gapped install, which OpnForm's docs list among the reasons to self-host.
On a vendor's cloud, the vendor handles responses on behalf of whoever runs the survey. Under the GDPR that makes it a processor, and Article 28 requires a contract between the two. LimeSurvey's pricing grid lists this data processing agreement on its paid plans, not on the free one. You pick the hosting country when the instance is created, with Germany and Finland recommended for EU customers, and responses stay there. Formbricks hosts its cloud in Frankfurt and publishes its DPA: the database runs on AWS in Germany, but the subprocessor list also includes Cloudflare, listed as global, for the CDN, and Stripe, in the United States, for payments. All three vendors are based in Europe: LimeSurvey GmbH in Hamburg, Formbricks GmbH in Kiel, and OpnForm in France. OpnForm describes its cloud as EU-based, but its privacy policy names no hosting country and no subprocessor.
A LimeSurvey survey can be set to anonymized responses: answers are then no longer linked to the participant table, and their dates are reset to 1 January 1980. Formbricks' free edition doesn't identify users, so an in-app survey reaches whoever triggers the action and never ties the answer to a known person. Identification, contacts and segments are paid features.
Where the projects stand
LimeSurvey has been developed since 2006 and moved to a new major version this year. Version 7.0.0 shipped on 26 May 2026, and 7.1.0 to 7.4.0 followed between 13 and 28 September. Its roadmap plans a patch every Monday and a minor release roughly every eight weeks, with fixes for version 7 until May 2028, then security fixes only until May 2029. Community Edition support for version 6 ended on 31 August 2026, and the upgrade takes some preparation: version 7 renames response tables and fields, which affects any plugin, theme or reporting query that reads them directly.
Formbricks has shipped eleven minor or major releases since January, including 5.0.0 on 27 May and 6.0.0 on 21 September 2026. Each minor version gets fixes for three months, and only the newest one gets non-security fixes, so 6.0 is covered until 21 December 2026. Its README says code contributions are, for now, accepted only as an exception.
OpnForm published twelve releases between 2.0.0 on 8 June and 2.5.0 on 2 September 2026, and its main branch still gets commits, the latest on 6 October. One maintainer accounts for 865 commits, the next contributor for 344.
Licences and paid plans
LimeSurvey is under GPL-2.0 or later, with no proprietary directory. The GPL only requires you to publish your changes when you distribute the software, so running a modified version online doesn't trigger it, unlike the AGPL used by Formbricks and OpnForm. The vendor sells one-click updates from the admin interface, ComfortUpdate, at €59 for six months or €99 for a year. Its cloud is priced by response volume, VAT included: 25 a month on the free plan, with the survey locked until the next month once the quota runs out, 1,000 a month for €34 on Basic, up to 50,000 a year for €900 on Business. SSO, LDAP and SAML only appear on the Corporate plan, priced on request, while the Community Edition ships an LDAP plugin, two-factor login for administrators and an audit log. The vendor's community page does advertise some features as exclusive to LimeSurvey Cloud.
Formbricks and OpnForm put their core under AGPL-3.0 and keep one directory under a proprietary licence, shipped in the Docker images and unlocked with a key: apps/web/modules/ee for Formbricks, api/app/Enterprise/ for OpnForm. You may modify and test that code, but running it in production takes a licence. For Formbricks, the licence covers user identification, segments, OIDC and SAML SSO, two-factor authentication, roles, audit logs and spam protection. Keeping your changes to the core private is a paid right too, and since version 6 the free edition gets a single workspace. Self-hosted pricing is on request. The Formbricks cloud is free up to 250 responses a month, then $74 a month for 2,000. OpnForm's self-hosted licence costs $1,999 a year per instance: it lifts the two-account cap that came with version 2, opens up SAML, LDAP, roles and audit logs, and removes OpnForm branding. OIDC stays free within the two-account limit. OpnForm's free cloud plan caps neither forms nor responses but keeps the branding; custom domains and captcha start at $25 a month, and the vendor recommends its cloud for most users.