# Finowl

> Developer documentation for the Finowl API: email and password breach checks and gender prediction from names, emails and usernames.

- [Finowl API](https://docs.finowl.co/index.md): Check emails and passwords against known breaches and predict gender from names, emails and usernames, with one simple JSON API.
- [Quickstart](https://docs.finowl.co/quickstart.md): Create an API key and make your first Finowl request in under 5 minutes.
- [Authentication](https://docs.finowl.co/authentication.md): Authenticate every request with a secret API key sent as a bearer token.
- [Credits and billing](https://docs.finowl.co/concepts/credits.md): How Finowl counts credits, when a request is charged and how to top up.
- [Rate limits](https://docs.finowl.co/concepts/rate-limits.md): How many requests you can send, and how to stay under the limit.
- [Errors](https://docs.finowl.co/concepts/errors.md): Every error code the Finowl API returns, what it means and how to handle it.
- [Retries and reliability](https://docs.finowl.co/concepts/retries.md): When it is safe to send a request again, and how to do it without paying twice.
- [Data handling and privacy](https://docs.finowl.co/concepts/data-privacy.md): What Finowl does with the data you send, and what you need to tell your users.
- [Block breached passwords at sign up](https://docs.finowl.co/guides/password-checks-at-signup.md): Stop users from choosing passwords that already appear in breach lists, without slowing down sign up.
- [Email breach monitoring](https://docs.finowl.co/guides/email-breach-monitoring.md): Detect when your users' email addresses appear in new data breaches and prompt them to secure their accounts.
- [Enrich a contact list](https://docs.finowl.co/guides/batch-gender-enrichment.md): Add gender estimates to thousands of CRM contacts with the batch endpoint, safely and efficiently.
- [Reading predictions](https://docs.finowl.co/guides/interpreting-predictions.md): How to interpret gender predictions, use confidence and AI modes, and handle unknown results responsibly.
- [API reference](https://docs.finowl.co/api-reference/introduction.md): Base URL, authentication, request format and conventions shared by every Finowl endpoint.
- [Check an email](https://docs.finowl.co/api-reference/breaches/email.md): Find every known public data breach that included an email address.
- [Check a password](https://docs.finowl.co/api-reference/breaches/password.md): Find out how often a password appears in known data breaches, without exposing it.
- [Predict from a name](https://docs.finowl.co/api-reference/gender/name.md): Estimate gender from a first or full name, with optional country context.
- [Predict from an email](https://docs.finowl.co/api-reference/gender/email.md): Estimate gender from the name found in an email address.
- [Predict from a username](https://docs.finowl.co/api-reference/gender/username.md): Estimate gender from a username or social handle.
- [Predict in batch](https://docs.finowl.co/api-reference/gender/batch.md): Predict gender for up to 50 names, emails and usernames in one request.
- [Check an email](https://docs.finowl.co/api-reference/breaches/check-an-email.md): Returns every known public breach that included this email address, from Finowl intelligence.
- [Check a password](https://docs.finowl.co/api-reference/breaches/check-a-password.md): Returns how many times a password appears in known breaches, using Finowl intelligence. The password is never stored, logged or returned, and it is matched by partial hash (k-anonymity), so the full password or its full hash is never used in the lookup.
- [Predict from a name](https://docs.finowl.co/api-reference/gender/predict-from-a-name.md): Predicts gender from a first name or a full name with Finowl intelligence. Latin and non-Latin scripts are supported.
- [Predict from an email](https://docs.finowl.co/api-reference/gender/predict-from-an-email.md): Extracts a likely name from the email address and predicts gender from it.
- [Predict from a username](https://docs.finowl.co/api-reference/gender/predict-from-a-username.md): Looks for names, initials and separators inside a username and predicts gender when the signal allows. Set `forceToGenderize` to `true` for usernames that do not contain a recognizable name.
- [Predict in batch](https://docs.finowl.co/api-reference/gender/predict-in-batch.md): Predicts gender for 1 to 50 mixed inputs in one request. Results come back in the same order as `items`. A `200` response can contain individual item errors, so check each entry.

## OpenAPI Specs

- [openapi](/api-reference/openapi.yaml)


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