Formulix documentation
Connect your school or learning platform’s editor to the API and keep lesson content readable.
Get started
- Choose your platform guide below and install. The API URL comes filled in and the key is optional: the domain starts on the Free plan.
- When the limit runs out, follow the dialog’s link: create an account in the dashboard, register the domain and choose a plan. If you want a key, it is shown once; the database stores its hash and prefix.
- Insert an item, save, reload and edit it again. For graphs and drawings, also test PNG upload.
- Check HTML display on the student-facing page, outside the editor.
English classroom notation
Select en for the English interface. English is built into src/i18n.js; there is no separate English locale file. Defaults are decimal points (12.5), sin/tan, ordered pairs such as (2.5, -0.25), roots labelled x₁/x₂ and long division. In the interface, Set up calculation opens Addition, Subtraction, Multiplication and Division.
Teachers in the UK may know GCD (greatest common divisor) as HCF (highest common factor). “Rule of three” is the interface label for direct or inverse proportion. “Quadratic formula” and “Aufbau diagram” are used instead of the names common in Brazilian textbooks.
Key concepts
- Domain and public key
- Without a key, the API identifies the site by the Origin hostname: a registered domain uses its account’s plan; an unregistered one uses the Free plan counted by domain. With a key (optional, visible in the browser), the API checks the key and Origin against the account’s domains. It is not a server secret: software outside the browser can forge Origin.
- API
- Runs the core on the server and returns HTML, MathML, SVG or JSON. The client provides the interface and uploads PNGs to your platform’s storage.
- Preview
- A successful
/v1/calccall records a preview without using insertions. The requests-per-minute limit still applies. - Insertion
- An accepted
/v1/inserircall counts one per formula, calculation, graph or drawing. Word counts one per converted equation. Editing and confirming an existing item counts again.
Plans and usage
| Plan | Insertions/month | Price |
|---|---|---|
| Free | 500 | R$ 0 |
| Starter | 5,000 | R$ 49/month |
| School | 25,000 | R$ 189/month |
| Network | No numerical ceiling in the code | By contract |
Paid plans combine usage across the account’s domains. Free also has a per-domain ceiling across accounts; changing the key does not reset usage. Monthly periods follow UTC.
Development has a separate default quota of 300 insertions/month/account, configurable by the operator. It covers localhost, .localhost subdomains, 127.0.0.1, [::1] and .test domains, without using the plan quota. Without a key, this quota applies per IP.
12 months cost 10 monthly payments, paid upfront: Starter R$ 490, School R$ 1,890. See the terms of use.
Charged in Brazilian reais (BRL) via Mercado Pago; for other currencies, contact us.