Terms of Service

SayDiagram lets you create, edit, arrange, export, share, and embed Mermaid-based diagrams, including optional AI-assisted generation. Features and limits differ by Free, Pro, Student Pro, and Team plans as described on our pricing page.

You are responsible for activity under your account and for keeping login credentials secure. Provide accurate information and keep your email reachable for billing and security notices.

You retain ownership of diagrams and other content you create. You grant us a license to host, process, display, and transmit that content solely to operate and improve the service (including AI features you invoke, share links you enable, and embeds).

Do not upload content that is illegal, infringing, malicious, or that you do not have rights to use. We may remove content or suspend accounts that violate these terms or harm the service.

• No abuse of AI, export, or sharing limits via automation intended to evade plan caps
• No attempts to disrupt, scrape at abusive rates, or reverse-engineer the service beyond what’s allowed by law
• No using SayDiagram to distribute malware or violate others’ rights

Paid subscriptions are billed through Stripe. Fees, intervals, and taxes are shown at checkout. Unless required by law, payments are non-refundable once a billing period has started. You can manage or cancel renewal through the billing portal on your profile. Student Pro offers may have additional eligibility rules (for example .edu email).

SayDiagram uses Mermaid.js for rendering, Stripe for payments, and supports export workflows to design tools such as Figma (including the SayDiagram Figma / FigJam Community plugin), Penpot, and Excalidraw via SVG/PNG copy. Those products are owned by their respective companies. SayDiagram is not affiliated with or endorsed by Mermaid Chart, Figma, Penpot, Excalidraw, or Stripe beyond being a customer/user of their services where applicable. Use of third-party marks on our site indicates compatibility or payment processing only.

AI outputs may be inaccurate or incomplete. You are responsible for reviewing generated diagrams before relying on them. Do not submit sensitive personal data in prompts or scans unless you accept that it may be processed by our AI providers.

The service is provided “as is” without warranties of any kind to the fullest extent permitted by law. To the maximum extent permitted by law, SayDiagram’s total liability for any claim relating to the service is limited to the amounts you paid us in the three months before the claim (or zero if you are on Free).

You may stop using the service at any time. We may suspend or terminate access for violations of these terms, non-payment, or risk to the platform. Provisions that should survive (including ownership, disclaimers, and liability limits) will survive termination.

We may update these terms. Continued use after changes take effect constitutes acceptance. The date at the top will be updated when we post changes.

Questions: hello@saydiagram.com

See also our Privacy Policy.