Base64 Guides & Tutorials

CLINew base64 Command (Linux & macOS) Flags, GNU vs BSD differences, -w 0 line wrapping, and shell pipeline patterns. TroubleshootingNew Fix Invalid Base64 Errors Diagnose and fix padding errors, whitespace issues, and wrong variant errors across all languages. Use CaseNew HTTP Basic Auth & Base64 How Basic Authentication encodes credentials in the Authorization header, with security warnings. ConceptsNew Base64 vs Base32, Base58 & Base85 Compare all binary-to-text encoding schemes: size overhead, alphabet, and when to use each. CLINew OpenSSL Base64 openssl enc -base64, the critical -A no-linebreak flag, and certificate workflows. DevOpsNew SSH Keys & PEM Certificates Encode private keys for env vars, Docker, Kubernetes, and CI/CD pipelines. Use CaseNew Base64 File Upload in React Convert files and images to Base64 with FileReader in React, with TypeScript types. CNew Base64 in C Lookup-table encoder/decoder implementation, URL-safe variant, and OpenSSL EVP API. BashNew Base64 in Bash Scripts The echo -n newline gotcha, file encoding, env variables, and multi-line handling. ConceptsNew Base64 Padding Explained Why = signs exist, how padding is calculated from input length, and when it can be omitted. PowerShellNew Base64 in PowerShell [Convert]::ToBase64String, the UTF-16 encoding trap, and cross-platform usage. DartNew Base64 in Dart & Flutter dart:convert base64 and base64Url codecs, image encoding, and HTTP usage. Use CaseNew Binary Data in JSON How and when to embed binary in JSON with Base64 — tradeoffs and multipart alternatives. C++New Base64 in C++ std::string implementation, Boost.Beast base64, and OpenSSL EVP API. Concepts What is Base64 Encoding? A complete explanation of the Base64 scheme, the 64-character alphabet, padding, and when to use it. Concepts URL-Safe Base64 (RFC 4648) How URL-safe Base64 differs from standard Base64, and when to use it in JWTs, URLs, and filenames. Use Case Image to Base64 Data URI Embed images directly in HTML and CSS using Base64 data URIs. When to use them and when to avoid. Use Case Base64 in JSON Web Tokens (JWT) How JWTs use Base64URL encoding for headers, payloads, and signatures. Concepts Base64 vs Hex Encoding When to choose Base64 over hexadecimal encoding, and vice versa. Size comparison and use cases. Use Case Base64 Data URIs Explained The data: URI scheme in depth — syntax, MIME types, browser support, and performance. JavaScript Base64 in JavaScript btoa(), atob(), TextEncoder, Buffer in Node.js, and handling Unicode strings correctly. TypeScript Base64 in TypeScript Type-safe Base64 encoding and decoding in TypeScript for browser and Node.js environments. Node.js Base64 in Node.js Using Node.js Buffer to encode and decode Base64 strings, files, and streams. Python Base64 in Python The base64 module, b64encode/b64decode, URL-safe variants, and encoding binary files. Java Base64 in Java java.util.Base64 — basic, URL-safe, and MIME encoders in Java 8+. Go Base64 in Go encoding/base64 package — StdEncoding, URLEncoding, RawURLEncoding, and byte slices. Rust Base64 in Rust Using the base64 crate Engine API with standard and URL-safe alphabets. PHP Base64 in PHP base64_encode(), base64_decode(), URL-safe Base64, and encoding binary file data. C# Base64 in C# (.NET) Convert.ToBase64String, FromBase64String, byte arrays, streams, and URL-safe Base64. Ruby Base64 in Ruby encode64 vs strict_encode64 vs urlsafe_encode64 and the critical differences. Swift Base64 in Swift Data.base64EncodedString() and Data(base64Encoded:) for iOS and macOS apps. Kotlin Base64 in Kotlin java.util.Base64 in Kotlin, multiplatform approaches, and Ktor utilities.