Noun Project
Icons
Noise Background Image Generator.
PHP-Noise API is a free Art & Design API that requires no API key, is served over HTTPS and supports CORS, so it can be called from the browser.
PHP-Noise is a free and Open Source «Noise Background Image» generator which allows you to create your very own background images.
Details from php-noise.com.

Unified API suite · now live
Geocode an address, validate an email, track a flight or pull stock data with one account, one dashboard and one API key.
Icons
SVG Icon Generator
Yes. The PHP-Noise API is listed in the Art & Design 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.
No. The PHP-Noise API requires no authentication, so you can start making requests without signing up.
Yes. The PHP-Noise API supports CORS, so front-end JavaScript can call it directly.
Yes. The PHP-Noise API is served over HTTPS, so it's safe to use in production.