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UTF-8 Encode/Decode
Tool Description
UTF-8 Encode/Decode is an online UTF-8 encoding/decoding tool that can convert text into UTF-8 hexadecimal byte sequences or restore hex byte sequences back to original text. UTF-8 is the most widely used character encoding on the internet, supporting all languages worldwide. The tool uses the browsers native TextEncoder/TextDecoder APIs — all operations run locally in your browser, no data is ever uploaded to any server.
How to Use
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Enter Content
Enter or paste the text or UTF-8 hex byte sequence you want to process in the left input box
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Choose an Action
Click the "Encode" button to convert text to a UTF-8 hex byte sequence (e.g. "你好" →
E4 BD A0 E5 A5 BD), or click "Decode" to restore hex bytes to original text -
Save the Result
The encoded/decoded result will appear in the right output box. Click "Copy" to copy the result, or "Download" to save it as a text file
Use Cases
- Encoding Learning & Research: Visually inspect the UTF-8 byte representation of Chinese, Japanese, Emoji, and other characters to understand the Unicode-to-UTF-8 conversion process
- Development Debugging: Quickly obtain the UTF-8 hex representation of any text for protocol debugging, network packet analysis, and database encoding troubleshooting
- Data Recovery: Restore UTF-8 hex byte sequences from logs or captured network data back to readable text for quick issue diagnosis
Key Advantages
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Global Character Support
UTF-8 supports virtually every written language — Chinese, Japanese, Korean, Arabic, Emoji, and more are all encoded/decoded correctly
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Free Daily Usage
Free daily usage is provided for every user, so routine encoding needs can be met at zero cost; frequent or professional use can unlock more quota by subscribing to membership
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Privacy & Security
All encoding and decoding run entirely in your browser; your data is never uploaded to any server, providing 100% privacy protection
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Encode & Decode
Supports both text → hex bytes and hex bytes → text, with a built-in swap button to quickly switch directions
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Multiple Delimiter Support
When decoding, automatically recognizes spaces, commas, semicolons, and newlines, making it easy to paste hex data from anywhere
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No Installation Needed
No installation or registration required; open your browser and use it right away, compatible with PC and mobile platforms
UTF-8 Encoding Rules
UTF-8 is a variable-length encoding that uses 1 to 4 bytes to represent a Unicode character. The encoding rules are:
| Unicode Range | Bytes | Byte Format |
|---|---|---|
| U+0000 ~ U+007F | 1 | 0xxxxxxx |
| U+0080 ~ U+07FF | 2 | 110xxxxx 10xxxxxx |
| U+0800 ~ U+FFFF | 3 | 1110xxxx 10xxxxxx 10xxxxxx |
| U+10000 ~ U+10FFFF | 4 | 11110xxx 10xxxxxx 10xxxxxx 10xxxxxx |
UTF-8 vs Other Encodings
Comparison of three Unicode encoding schemes — UTF-8, UTF-16, and UTF-32:
| Feature | UTF-8 | UTF-16 | UTF-32 |
|---|---|---|---|
| Encoding Unit | 1~4 bytes (variable-length) | 2~4 bytes (variable-length) | 4 bytes (fixed-length) |
| ASCII Compatibility | Fully compatible (0x00~0x7F unchanged) | Not compatible, ASCII chars use 2 bytes | Not compatible, ASCII chars use 4 bytes |
| Space Efficiency | Best (English 1 byte, Chinese 3 bytes) | Moderate (English 2 bytes, Chinese 2 bytes) | Worst (all chars 4 bytes) |
| Use Cases | Web, Linux, databases, APIs | Windows internals, Java strings | Internal character processing, fixed-width indexing |
FAQ
UTF-8 (8-bit Unicode Transformation Format) is a variable-length character encoding for the Unicode character set. It uses 1 to 4 bytes per character, is fully compatible with ASCII (letters and digits use 1 byte), Chinese characters use 3 bytes, and special characters like Emoji use 4 bytes. UTF-8 is the most widely used character encoding on the internet, with over 98% of web pages using UTF-8 encoding.
UTF-8 is a character encoding that defines how to map characters to byte sequences (e.g. '你' → E4 BD A0). Base64 is a transport encoding that defines how to represent byte sequences as printable characters. They solve different problems: UTF-8 addresses "how characters are stored as bytes", while Base64 addresses "how bytes are safely transmitted in text protocols".
In UTF-8, the byte length depends on the character's Unicode code point range. Most Chinese characters fall in the U+0800 ~ U+FFFF range, which requires 3 bytes according to UTF-8 encoding rules (format: 1110xxxx 10xxxxxx 10xxxxxx). Japanese and Korean characters are also in the same range and also use 3 bytes.
No. All encoding/decoding operations run entirely in your browser using the native TextEncoder and TextDecoder APIs. Your data never leaves your device.
Please enter two-digit hex numbers (00 ~ FF), separated by spaces, commas, semicolons, or newlines. For example: E4 BD A0 E5 A5 BD or E4,BD,A0,E5,A5,BD. The tool automatically ignores extra whitespace and separators for easy copy-paste.
Common reasons: ① The input hex byte sequence is not valid UTF-8 encoding (the byte combination does not conform to UTF-8 encoding rules); ② The original text used a different encoding (e.g. GBK, Shift-JIS) — decoding those bytes as UTF-8 will produce garbled text; ③ The byte sequence is incomplete, with missing bytes causing decoding failure. Please verify the encoding format of the original text.
This tool provides free daily usage, so routine lightweight needs can be met at zero cost. No registration or login is required — just open the page and use it. When you need higher processing volumes or more frequent use, subscribing to membership unlocks more benefits to handle various scenarios with ease.
Both are character encodings, but with different encoding rules: UTF-8 is a variable-length Unicode encoding that covers virtually every character in the world — Chinese characters take 3 bytes, and it is the standard for the Web and international use; GBK is a Chinese-specific encoding where Chinese characters take 2 bytes, used mainly within China. Decoding GBK bytes as UTF-8 produces garbled text and vice versa. This tool processes data in UTF-8.
In UTF-8: English letters/digits take 1 byte (fully ASCII-compatible); Chinese characters take 3 bytes; some rare characters and Emoji take 4 bytes. For example, "Hello" encodes to 48 65 6C 6C 6F (5 bytes), while "你好" encodes to E4 BD A0 E5 A5 BD (6 bytes).
Absolutely. Emoji and some rare characters occupy 4 bytes in UTF-8 (e.g., F0 9F 98 80). The tool correctly encodes and decodes any Unicode character, including emoji, mathematical symbols, and characters from various writing systems.
Enter two-digit hexadecimal numbers (00 to FF) separated by spaces, commas, semicolons, or newlines. For example, E4 BD A0 E5 A5 BD or E4,BD,A0,E5,A5,BD. The tool automatically ignores extra whitespace and separators, and accepts both upper- and lowercase.
No. Many character encodings exist (GBK, UTF-16, ISO-8859-1, etc.), and there is no "single correct" encoding — what matters is that encoding and decoding use the same one. UTF-8 is the Web standard because it is ASCII-compatible, space-efficient, and supports all Unicode characters. This tool focuses on UTF-8, helping you verify and process UTF-8 encoded data.
Content last updated：2026-07-16
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