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Public APIs · by APILayerData from public-apis (MIT)
  1. Home
  2. /Finance
  3. /Undertow
Finance
U

Undertow

Public market-depth and sized exit estimates, not executable quotes.

Undertow API is a free Finance API that requires no API key, is served over HTTPS and supports CORS, so it can be called from the browser.

Authentication
None required
HTTPS
Yes
CORS
Yes
Category
Finance
Visit documentation ↗liquilens-undertow.com

About Undertow · by LiquiLens

Read-only API, MCP and x402 access to the liquidity board, exit costs and sealed evidence record.

Provider
Undertow · by LiquiLens
Website
liquilens-undertow.com ↗

Details from liquilens-undertow.com.

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Undertow API alternatives

Twelve Data logo

Twelve Data

Stock market data (real-time & historical)

apiKeyHTTPSCORS ?
US Mortgage Calculator logo

US Mortgage Calculator

Mortgage payment, amortization, affordability and 50-state property tax data

No authHTTPSCORS
Tradier logo

Tradier

US equity/option market data (delayed, intraday, historical)

OAuthHTTPSCORS
VAT Validation logo

VAT Validation

Validate VAT numbers and calculate VAT rates

apiKeyHTTPSCORS
Top 5 Stocks logo

Top 5 Stocks

Daily AI-ranked stock and crypto watchlists

No authHTTPSCORS ?
VoxOdds logo

VoxOdds

Polymarket and Kalshi odds, all-in executable quotes, EV checks and audited forecast scores

No authHTTPSNo CORS

Undertow API FAQ

Who provides the Undertow API?

The Undertow API is provided by Undertow · by LiquiLens (liquilens-undertow.com). Read-only API, MCP and x402 access to the liquidity board, exit costs and sealed evidence record.

Is the Undertow API free?

Yes. The Undertow API is listed in the Finance category of the public-apis directory, which only includes APIs that are free or have a free tier. Check its documentation for rate limits and paid plans.

Does the Undertow API require an API key?

No. The Undertow API requires no authentication, so you can start making requests without signing up.

Can I call the Undertow API from the browser?

Yes. The Undertow API supports CORS, so front-end JavaScript can call it directly.

Does the Undertow API support HTTPS?

Yes. The Undertow API is served over HTTPS, so it's safe to use in production.