taxapi.net

What It Is

Simple Income Tax API is a very lightweight income tax calculation API. Its main goal is to make it easier to calculate income tax in spreadsheets. A typical use case is calling a URL such as https://api.taxapi.net/income/single/50000/2020 via Google Sheets’ IMPORTDATA, passing in filing status, MAGI, and tax year.

Core Features and API

The API supports only a small but clear set of parameters: status can be single, married, or hoh; the income input should be MAGI, meaning modified adjusted gross income, rather than gross income; year is optional, and if omitted, the API defaults to the latest year it currently supports. The documentation also notes that you can request an invalid year to see the supported years. Overall, this feels more like a purpose-built HTTP endpoint for spreadsheet users than a full developer platform; the text does not mention SDKs, authentication, response formats, error codes, or rate limits.

Integration, Ecosystem, and Documentation

For integration, the page focuses on Google Sheets: you can fetch data directly with IMPORTDATA, or use CONCAT to assemble the URL from spreadsheet cells, making it suitable for financial modeling sheets or personal tax estimate sheets. The tax bracket data source is listed as NerdWallet, with an indication that it will be updated in the future as brackets change. The documentation is short and straightforward, covering basic usage, an explanation of MAGI, and simple troubleshooting, but it lacks production-grade API details such as versioning, SLA, changelog, and data validation notes.

Pricing and Deployment

The captured text does not disclose pricing, payment methods, call limits, account system, or whether there are open-source or self-hosting options. As a result, it is difficult to assess its commercial sustainability or suitability for enterprise procurement. If used for critical workflows, you should independently verify its stability, accuracy, and long-term maintenance.

Pros, Cons, and Best Fit

Its strengths are extreme simplicity and the lack of complex integration requirements, especially for spreadsheet users who want to replace complicated VLOOKUP-based tax bracket formulas. Its limitations are a narrow scope, mainly centered on the U.S. income tax context, and insufficient public information to evaluate compliance, availability, or support capabilities. It is suitable for individuals, indie developers, or lightweight internal calculations; it is less suitable as the sole calculation basis for a serious tax system.

Access from China

The text does not provide information about access from mainland China, payment availability, or mirrors, so real-world connectivity is unknown. If access is unstable, alternatives include building tax bracket formulas directly in the spreadsheet, using a local script, or choosing a tax API with a clear SLA and documentation.