# NameGender

> NameGender is a name-to-gender API and managed spreadsheet service. It returns a statistical association together with probability, evidence count, confidence, country and source, and it can return unknown when evidence is insufficient.

Name-based inference does not identify an individual's gender. Preserve unknown results and evidence fields. Do not use inferred gender for employment, medical, financial, insurance, legal or eligibility decisions.

The public website and the resources below are in English unless a locale-specific URL is provided. The REST API is versioned under /api/v1, uses JSON, and takes the API key in an Authorization: Bearer or X-Api-Key header. Purchased credits remain available until used.

## API and product

- [API documentation](https://namegender.com/docs): Authentication, endpoints, request fields, response fields, errors and code examples.
- [OpenAPI specification](https://namegender.com/openapi.json): Machine-readable REST API contract.
- [Full API reference for AI assistants](https://namegender.com/llms-full.txt): Every endpoint, field, error code and implementation rule in one Markdown file, generated from the OpenAPI contract.
- [Gender API overview](https://namegender.com/gender-api): Product behaviour, inputs, response evidence, limits and quick start.
- [Pricing](https://namegender.com/pricing): Current plans, credit quantities and billing terms.
- [API changelog](https://namegender.com/changelog): Dated list of endpoint, field, behaviour and data changes, plus the versioning and deprecation policy.
- [Name gender](https://namegender.com/name-gender): What a name's gender measures, unisex names with official US shares (Riley 57% female, 1880-2024), names that flip by country (Jean: 95% female in the US, 100% male in France) and names whose gender changed over time.
- [Name gender checker](https://namegender.com/name-gender-checker): Rate-limited public checker for one name with an optional country code.
- [Name gender database](https://namegender.com/gender-database): Data sources, counted and uncounted evidence, provenance and update model.
- [Gender dataset guide](https://namegender.com/gender-dataset): Dataset fields, delivery choices, licensing questions and evaluation method.

## AI implementation instructions

Per-endpoint Markdown for coding assistants: contract, example requests, error handling, retry rules and a verification checklist.

- [Gender from a name](https://namegender.com/docs/ai/name.md)
- [Gender from an email address](https://namegender.com/docs/ai/email.md)
- [Gender from a username](https://namegender.com/docs/ai/username.md)
- [Bulk lookups](https://namegender.com/docs/ai/bulk.md)
- [Country distribution](https://namegender.com/docs/ai/countries.md)
- [Account and credits](https://namegender.com/docs/ai/account.md)

## Integration guides

- [Python](https://namegender.com/gender-api-python): Python client setup, single and bulk lookups, null handling and retries.
- [JavaScript](https://namegender.com/gender-api-javascript): Node.js, Deno and Bun usage, server-side key handling and bounded batching.
- [PHP](https://namegender.com/gender-api-php): PHP client setup, framework integration, queues and error handling.
- [Excel](https://namegender.com/gender-api-excel): XLSX/CSV upload and Power Query guidance.
- [Google Sheets](https://namegender.com/gender-api-google-sheets): Add-on and Apps Script workflow, credential handling and range-based processing.
- [Client libraries](https://namegender.com/client-libraries): Current official packages, installation commands and source repositories.
- [MCP server](https://namegender.com/docs#mcp): Use NameGender from Claude, Cursor and other Model Context Protocol clients through the namegender-mcp npm package (registry name io.github.anpekesen/namegender).

## Methods and comparisons

- [NameGender Research](https://namegender.com/research): Index of measured reports, methods and disclosed limitations.
- [Gender Prediction API Benchmark 2026](https://namegender.com/research/gender-api-benchmark-2026): Results for 4,610 labelled names across 25 countries, split by country and writing system.
- [Benchmark methodology](https://namegender.com/research/methodology): Coverage, accuracy and end-to-end definitions, holdout rules, reproducible commands and limitations.
- [Names that change gender by country](https://namegender.com/research/names-that-change-gender-by-country): Open CC BY 4.0 dataset from official name counts in twelve national registers across ten countries (479 names flip); names such as Jean, Andrea, Kim and Toni that are mostly girls in one country and mostly boys in another. CSV: https://namegender.com/datasets/names-gender-by-country.csv
- [How accurate is gender prediction from a name?](https://namegender.com/blog/how-accurate-is-gender-prediction-from-a-name): Coverage, accuracy when answered and end-to-end results by writing system, and how well the probability field is calibrated.
- [65 names that change gender by country](https://namegender.com/blog/names-that-change-gender-by-country): Names recorded as mostly male in one country and mostly female in another, from counted birth registrations.
- [How to compare gender APIs](https://namegender.com/blog/how-to-compare-gender-apis): Reproducible evaluation using coverage, accuracy when answered and end-to-end accuracy.
- [Best gender APIs in 2026](https://namegender.com/blog/best-gender-apis): Date-stamped shortlist and buyer's test.
- [Genderize alternatives](https://namegender.com/blog/genderize-alternatives): Migration criteria and shadow-testing method.
- [Gender API comparison](https://namegender.com/blog/gender-api-comparison): Comparison worksheet for evidence, country handling, throughput, billing and privacy.
- [Coverage by writing system](https://namegender.com/blog/coverage-by-script): Published fixture results and known gaps by script.
- [Probability and evidence fields](https://namegender.com/blog/probability-confidence-and-sample-size): How to interpret probability, confidence and sample_size.

## Name profiles

- [Name gender profiles](https://namegender.com/names): Curated names with country-level classification, probability, sample size and source.
- [Andrea](https://namegender.com/name/andrea/gender), [Jean](https://namegender.com/name/jean/gender), [Kim](https://namegender.com/name/kim/gender), [Deniz](https://namegender.com/name/deniz/gender), [Ayşe](https://namegender.com/name/ayse/gender): Country-aware examples where evidence and naming context are shown together.

## Optional

- [Bulk gender detection](https://namegender.com/bulk-gender-detection): CSV/XLSX workflow, deduplication and output design.
- [Customer data enrichment](https://namegender.com/gender-enrichment): Backfill and ongoing enrichment patterns.
- [Full-name processing](https://namegender.com/gender-from-full-name): Given-name extraction and naming-order limitations.
- [Email processing](https://namegender.com/gender-from-email): Mailbox parsing and evidence limits.
- [Username processing](https://namegender.com/gender-from-username): Username token extraction and conservative null handling.
- [Service status](https://namegender.com/status): Current public component status.
- [Privacy policy](https://namegender.com/privacy-policy): Current privacy terms.
- [Data processing agreement](https://namegender.com/data-processing-agreement): Data-processing terms for customers.