MonitoringLangfuse and the GDPR: agreement, role and data location.
Langfuse is a monitoring tool. Most customers use it as a processor, it publishes its data processing agreement, and the data location depends on your account. Below: what to check and how to declare it.
Prefilled for you · Free to set up · No credit card
In short
- Category
- Monitoring
- Usual role
- Usually a processor
- Data location
- Often Customer-selected region, check your account
- Agreement
- Published by the vendor
What does Langfuse do with personal data?
Monitor application reliability, investigate errors and diagnose incidents. That is how Privacyboard describes a typical use of Langfuse, as a starting point you can edit.
The data usually involved: error events, request metadata, IP addresses, user identifiers and application logs where configured.
Is Langfuse a processor or a controller?
Most customers use Langfuse as a processor: it handles personal data on their instructions, for the purposes they set. That is the common reading for monitoring tools and it is what Privacyboard suggests.
As a processor, it needs a written agreement with you under Article 28, and you should know which subprocessors it uses. Confirm the role against your own agreement, because the way you use a tool can change it.
Where does Langfuse store personal data?
Langfuse is usually associated with Customer-selected region, but the location can depend on your plan or settings. Privacyboard prefills it as a starting point that you should check in your account.
What Langfuse says (read on 2026-11-05): Hosted in the region selected by Customer as set forth on an Order Form Source: https://clickhouse.com/legal/agreements/data-processing-addendum
How to find yours: Look at the address you log in to or your project settings.
If the data is processed outside the European Economic Area, Articles 44 to 49 require a transfer mechanism, such as standard contractual clauses, an adequacy decision or the EU-US Data Privacy Framework. Your privacy policy should name it.
Which legal basis usually applies to Langfuse?
For the usual use of Langfuse, companies most often rely on legitimate interests (GDPR Article 6(1)). Error and performance monitoring protects the service, and people reasonably expect it.
The interest you would state: “Detecting and fixing errors and keeping our service reliable and secure.” The GDPR asks you to say which interest you pursue (Article 13(1)(d)).
The balancing test is yours to do: the interest must be real, the processing necessary for it, and people’s rights must not outweigh it.
This is a starting point, not legal advice: the basis belongs to your activity, and you confirm it in your register.
Sources: GDPR Article 6, lawfulness of processing, EDPB Guidelines 1/2024 on legitimate interest
Does Langfuse have a data processing agreement?
Checked on 5 November 2026. Vendors change their pages, so check the date.
Yes. Langfuse publishes the text of its data processing agreement on its own website. Article 28 of the GDPR requires a written contract with every processor, so this is the document to read and keep.
What we noted when we opened the page: langfuse.com/security/dpa redirects to the ClickHouse Customer Data Processing Addendum, effective 10 Apr 2026, covering Langfuse Cloud. Data hosted in the customer-selected region; EU SCCs, UK Addendum, Swiss terms and the DPF.
A page that exists does not mean you are covered. Whether the agreement applies to you depends on your plan and on what you accepted, so record the decision yourself in your vendor list.
Read the Langfuse agreementHow to declare Langfuse
- 1
In your privacy policy
Name Langfuse as a recipient, say what it is used for (monitor application reliability, investigate errors and diagnose incidents) and mention any transfer outside the EEA. Articles 13 and 14 ask you to tell people who receives their data.
- 2
In your vendor list
Add Langfuse with its purpose, the data involved, its role, its region and a link to the agreement. Privacyboard prefills all of this, you confirm or correct it.
- 3
In your processing register
Link Langfuse to the activities that use it, so each record shows its recipients. Article 30 asks the register to list the categories of recipients.
What to check before relying on Langfuse
- Check what is sent by default, and scrub personal data from logs and error payloads.
- Set a retention period that matches how long you need the logs.
- Record the region where events are stored.
- List the tool as a recipient if user identifiers reach it.
Go online for free. Grow when you need to.
Free puts you online. Pro adds requests, domains and your team; Business, your brand only.
Free
$0 forever
No card, no time limit
For getting compliant and going online on your own.
Start for freeKey features:
- Privacy and cookie policies
- Vendor and processing registers
- Requests and breaches tracked
- Impact assessment screening
- Privacy center on privacyboard.io
- Cookie banner on 1 domain
- 1 person
No card needed
ProRecommended
$32 per month
Billed $384 a year Save $84
For taking requests, covering all your sites and working as a team.
Start with ProEverything in Free, plus:
- DPA for your clients
- PDF and Excel exports
- Email reminders
- Request form and replies
- Your own domain
- Banner on 3 domains, every choice logged
- Weekly site scan
- Complete DPIAs and TIAs
- AI assistant connector
- Up to 5 people, with roles
Cancel any time
Business
$109 per month
Billed $1,308 a year Save $240
For proving it to customers and auditors, under your brand only.
Start with BusinessEverything in Pro, plus:
- No Privacyboard mention
- Security section and vendor alerts
- Evidence pack in one click
- Banner on 10 domains, daily scan
- Up to 50 people
- Two-step verification required
- Activity log kept 3 years
Bank transfer on request
Questions, answered.
Is Langfuse GDPR compliant?
Privacyboard does not certify vendors. Compliance depends on how Langfuse is configured and used, on the agreement you have with it and on your own practices. What can be checked is documented here: it publishes a data processing agreement, the usual role and the data location. Read the agreement itself before relying on it.
Does Langfuse have a DPA?
Yes. Langfuse publishes the text of its data processing agreement on its own website. Article 28 of the GDPR requires a written contract with every processor, so this is the document to read and keep. You can read it at https://clickhouse.com/legal/agreements/data-processing-addendum.
Is Langfuse a data processor?
Usually, yes. Most customers use Langfuse as a processor that acts on their instructions. Check your own agreement and how you use the tool, because the role can differ.
Which legal basis applies when I use Langfuse?
For the usual use of Langfuse, companies most often rely on legitimate interests (GDPR Article 6(1)). Error and performance monitoring protects the service, and people reasonably expect it. The interest you would state: “Detecting and fixing errors and keeping our service reliable and secure.” The GDPR asks you to say which interest you pursue (Article 13(1)(d)).
Where does Langfuse store data?
Langfuse is usually associated with Customer-selected region, but the location can depend on your plan or settings. Privacyboard prefills it as a starting point that you should check in your account. What Langfuse says (read on 2026-11-05): Hosted in the region selected by Customer as set forth on an Order Form Source: https://clickhouse.com/legal/agreements/data-processing-addendum
Do I need to mention Langfuse in my privacy policy?
Yes, if Langfuse handles personal data for you. The GDPR asks you to tell people who receives their data (Articles 13 and 14). Name the vendor or its category, say what it is used for and mention any transfer outside the EEA.
How do I add Langfuse to my vendor list?
In Privacyboard, pick Langfuse from the catalog. The purpose, the data, the suggested role and a link to its agreement are prefilled, and you confirm each one. Creating a workspace is free.
Similar tools
Privacyboard is not affiliated with Langfuse. Names and logos belong to their owners and are used only to identify the tool. This page summarises public documents as checked on 1 November 2026; it is guidance, not legal advice, and it does not certify any vendor.