Privacy Policy

Last updated September 29, 2026

Reason to Manim turns a math question you type into a short explainer video. Doing that means your question has to leave your browser and be processed by machines we rent from other companies. This page explains exactly what is collected, who touches it, and for how long — in plain language rather than legal boilerplate.

1. The short version

WhatWhyHow long
The question or topic you typeTo work out the answer and plan the video30 days
The video and the explanation we generateTo show and replay it for you30 days
Your IP address and browser detailsTo stop abuse and keep the service runningUp to 30 days
A language choice and a job reference, in your own browserTo remember your language and let you reopen a videoUntil you clear your browser storage

We do not require an account. We do not ask for your name, email address, or payment details. We do not use advertising or cross-site tracking cookies, and we do not sell personal information.

2. What we collect

2.1 What you submit

The text you type into the prompt box, and nothing else. The box is a single free-text field; there is no file upload, no microphone access, and no camera access. Please do not type personal information about yourself or anyone else into it — it becomes part of your request and is processed by the systems described in section 4.

2.2 What the service generates

The explanation text, the animation source code, and the finished video file. These are stored so that the video keeps playing when you refresh the page, close the tab, or open your link on another device.

2.3 Technical information

Like every website, our infrastructure provider records the request metadata needed to serve traffic and block abuse: IP address, browser user-agent string, the page or endpoint requested, and a timestamp. We also keep a short-lived per-IP counter so that one visitor cannot consume the whole service: the current allowance is a small number of generations per network every ten minutes, and the counter is discarded when the window closes.

2.4 Storage in your browser

We do not set cookies. We use two localStorage entries, described in full on the Cookie and Storage page: your language preference and the reference to your most recent video.

2.5 What we do not collect

3. Why we process it, and our legal basis

Where the EU or UK GDPR applies, we rely on the following legal bases:

PurposeLegal basis
Generating and delivering the video you asked forPerformance of a contract (Art. 6(1)(b))
Rate limiting, abuse prevention, and keeping the service availableLegitimate interests (Art. 6(1)(f)) — our interest in not having the service drained or attacked
Remembering your language choice in your browserStrictly necessary / your request (Art. 6(1)(b)); no consent required under the ePrivacy rules because you initiated it
Complying with legal obligations, or defending legal claimsLegal obligation (Art. 6(1)(c)) / legitimate interests (Art. 6(1)(f))

We do not use your submissions to train machine-learning models, and we do not build advertising profiles from them.

4. Who else processes it

We are a small operation and rely on the following processors. Each one receives only what it needs:

ProviderRoleWhat it receives
Cloudflare, Inc. Hosting, CDN, durable job state, video object storage The full request, your IP address, the generated video and code
DeepSeek (Hangzhou DeepSeek Artificial Intelligence Co., Ltd.) Language model that solves the problem, plans the video, and writes the animation code Your question text, the conversation so far, and the generated code
E2B (FoundryLabs, Inc.) Isolated cloud sandbox that renders the animation into a video file The generated animation code

We may also disclose information if we are legally required to, or to protect the rights and safety of users, the public, or ourselves. If the service is ever sold or merged, your information may transfer to the buyer under the same commitments in this policy.

A current list of sub-processors, and the data processing agreement we hold with each of them, is available on request from privacy@reason2m.com.

5. International transfers

We operate from the People's Republic of China and our processors store and process data in several countries, including the People's Republic of China, the United States, and the European Union. Where personal data leaves the EEA, the UK, or Switzerland, we rely on the European Commission's Standard Contractual Clauses (and the UK Addendum where relevant) together with the processors named above, and we assess each transfer for the risk of government access. You can request a copy of the relevant safeguards from privacy@reason2m.com.

6. How long we keep it

Because videos expire, a link you share will stop working after about 30 days. Re-run the question to generate a fresh one.

If you want your data removed sooner, email privacy@reason2m.com with the link or the job reference from your browser's address bar and we will delete it. We may keep a minimal record where the law requires us to.

7. Your rights

If you are in the EEA, the UK, or Switzerland, you have the right to: access your personal data; correct it; erase it; restrict or object to our processing; receive it in a portable format; withdraw consent where we relied on it; and lodge a complaint with your local supervisory authority.

If you are a California resident, you have the right to know what we collect, to request deletion, to correct inaccurate information, and not to be discriminated against for exercising those rights. We do not sell or share personal information as those terms are defined by the CCPA/CPRA, and we have not done so in the preceding twelve months.

Residents of other US states with comprehensive privacy laws (including Colorado, Connecticut, Virginia, Utah, and Texas) have equivalent rights, including appeal of our decision — reply to our decision email and we will escalate it to a human reviewer.

If you are located in the People's Republic of China, you additionally have the rights under the Personal Information Protection Law (PIPL), including the rights to know, access, correct, and delete your personal information, to request its transfer, and to withdraw consent.

To exercise any of these rights, email privacy@reason2m.com. We do not require an account to be created and we will not charge you for a reasonable request. We aim to respond within 30 days.

8. Children

Reason to Manim is not directed at children under 13, and we do not knowingly collect personal information from them. Because parts of the world require a higher age of digital consent, we set the minimum age at 16 for users in the EEA and the UK, and at 13 elsewhere (see the Terms of Service). We do not ask for an age and we do not use your question for anything other than producing your video — but if you believe a child has used the service, contact privacy@reason2m.com and we will delete the associated data.

9. Security

The service runs over TLS. Generated animation code is executed only inside an isolated third-party sandbox, never on our own infrastructure and never on your device. Access to production secrets is limited to the operators of the service. No system is perfectly secure, so please treat anything you type as potentially retained, and never submit confidential or sensitive information.

10. Changes

If we change how we handle personal data we will update this page and move the date at the top. Material changes — such as introducing analytics, accounts, or payments — will be announced on the service itself before they take effect.

11. Contact

The data controller is Reason to Manim, operated by an individual developer, reachable at privacy@reason2m.com.

Privacy questions, data requests, and sub-processor enquiries: privacy@reason2m.com.

General support: support@reason2m.com.