Base64 编解码工具Base64 Encode & Decode

文本与 Base64 互转（完整支持 UTF-8 中文）、URL-safe 模式；文件可转成 Base64 / Data URL，Base64 也能还原成文件下载，图片直接预览。全部在浏览器本地完成。Convert text to and from Base64 (full UTF-8 support) with a URL-safe mode; turn files into Base64 / Data URLs and decode Base64 back into downloadable files, with image previews. Everything runs locally in your browser.

文本编解码Text encode / decode

输入文本（编码时填明文，解码时填 Base64）Input (plain text to encode, or Base64 to decode)

URL-safe（- _ 替换 + /，去填充）

结果Result

文件 → Base64File → Base64

Base64 → 文件Base64 → File

粘贴 Base64（可以是纯 Base64，也可以是完整的 Data URL）Paste Base64 (raw, or a full Data URL)

保存文件名Save as filename MIME 类型（Data URL 里有则自动读取）MIME type (auto-read from a Data URL)

说明Notes

文本编码按 UTF-8 字节进行，所以中文、emoji 都不会乱码；解码时如果内容不是合法的 UTF-8 文本会给出错误提示，此时请改用下方的「Base64 → 文件」把它还原成文件。Text is encoded as UTF-8 bytes, so Chinese and emoji survive the round trip. If decoded bytes are not valid UTF-8 text you get an error instead of garbage — use Base64 → File below to recover the original file.