EstimateTax API
Overview
US federal, state and local income tax calculation for 2026, with the source of every figure
EstimateTax is a finance API. It needs no API key. It is served over HTTPS and allows browser requests (CORS).
At a glance
- Authentication
- No auth
- HTTPS
- Yes
- CORS
- Yes
- Category
- Finance
Questions
Does the EstimateTax API need an API key?
No. The EstimateTax API can be called without an API key or sign-up, which makes it handy for prototypes and front-end demos.
Can I call the EstimateTax API from the browser?
Yes. The EstimateTax API sends CORS headers, so a web page can call it directly with fetch().
Does the EstimateTax API support HTTPS?
Yes, the EstimateTax API is served over HTTPS.
What are alternatives to the EstimateTax API?
Other Finance APIs include Stripe, SEC EDGAR Data, Plaid, Fed Treasury, Razorpay IFSC.
Similar finance APIs
Compare alternatives →
Stripe
FinancePayment processing, subscriptions, and financial management
SEC EDGAR Data
FinanceAPI to access annual reports of public US companies
Plaid
FinanceConnect with user's bank accounts and access transaction data
Fed Treasury
FinanceU.S. Department of the Treasury Data
Razorpay IFSC
FinanceIndian Financial Systems Code (Bank Branch Codes)
Klarna
FinanceKlarna payment and shopping service
Listed from public-apis (MIT), Free Public APIs.