Understanding ECDSA Signatures with the Web Crypto API

Introduction Cryptographic techniques are used everywhere on the internet — TLS, SSH, email signatures, and more. Signing, verification, encryption, decryption, key exchange — these terms come up constantly, yet if asked whether I truly understood how they work, the honest answer was: not really. Then I discovered the Web Crypto API. It's a cryptographic API built into the browser that lets you perform crypto operations without any external libraries. The API is simple enough that you can learn by writing and running code. This motivated me to properly understand the fundamentals of cryptography at the code level. In this article, we'll look at digital signatures (ECDSA) and see how signing and verification actually work. What is the Web Crypto API? The Web Crypto API is a cryptographic API built into the browser. It allows you to perform key generation, signing, verification, encryption, and decryption without any external libraries. All operations are accessed through the crypto.subt