About This Article
This article was created using an automated generation workflow leveraging generative AI. It reviews .NET's Base64 conversion APIs and organizes them so you can observe encoding and restoration using only dummy strings.Verification Status: 📘 Confirmed with official .NET specifications, hardware testing not performed
Base64 is an encoding scheme that makes data easier to transport as strings. Because it can be reversed without a key, it does not substitute for encryption, which protects confidentiality.
Try It First
$text = 'papanda-demo'
$b64 = [Convert]::ToBase64String([Text.Encoding]::UTF8.GetBytes($text))
$b64
[Text.Encoding]::UTF8.GetString([Convert]::FromBase64String($b64))Look Here
The appearance of the string changes after encoding, but if papanda-demo is successfully restored at the end, it confirms reversibility. Since passwords can be restored in the same way, simply converting them to Base64 does not make them secure.
Change One Part
Try changing the string 'papanda-demo' in the script to Japanese text such as 'パンダ' and observe how the resulting Base64 string length and characters change.
Why It Works
Base64 is a representation format that maps binary data into ASCII characters. No decryption key exists, and anyone who knows the conversion rules can reverse it.
graph LR A[文字列] --> B[UTF-8 bytes] B --> C[Base64] C --> D[bytesへ復元] D --> E[元の文字列]
Practical Application
It is useful for representing binary data in places where it is difficult to handle directly, such as in emails or JSON. On the other hand, do not refer to putting tokens or passwords into configuration files as Base64 "encryption." To protect secrets, use OS credential stores, secret management services, or appropriate encryption methods.
Microsoft .NET Convert.ToBase64String: https://learn.microsoft.com/dotnet/api/system.convert.tobase64string
Microsoft .NET Convert.FromBase64String: https://learn.microsoft.com/dotnet/api/system.convert.frombase64string
この記事の更新履歴
この記事は、生成AIを活用した自動レビュー・更新フローにより内容を見直し、必要な修正を反映しています。
2026年9月23日
- 変更途中で途切れていた「Change One Part」の段落の日本語表現と手順を修正しました。
- 変更コードブロックの表示形式とHTML出力を整え、WordPress側で正しく表示されるように修正しました。
