Base64 to Hex
Decode Base64 or Base64URL to a hexadecimal string. Three output formats, exact byte count display — ideal for crypto debugging, signature verification, and low-level data analysis.
Hex Output
Output Format Reference
All three formats contain the same byte data, just presented differently.
e3b0c44298fc1c14Continuous lowercase string, pass directly to OpenSSL, hashlib, or other CLI tools.
e3 b0 c4 42 98 fc 1c 14Each byte separated by a space, useful for manual byte-by-byte comparison or code comments.
0xe3, 0xb0, 0xc4, 0x420x prefix with commas, paste directly into C arrays, Go slices, or JS Uint8Array literals.
Equivalent CLI Commands
Linux / macOS
echo "SGVsbG8=" | base64 -d | xxd -pOpenSSL
echo "SGVsbG8=" | openssl base64 -d | xxd -pPython 3
import base64
base64.b64decode("SGVsbG8=").hex()Node.js
Buffer.from("SGVsbG8=", "base64").toString("hex")Go
b, _ := base64.StdEncoding.DecodeString("SGVsbG8=")
fmt.Sprintf("%x", b)Frequently Asked Questions
Why convert Base64 to hex?
In cryptography, signature verification, and network protocol analysis, raw bytes are more readable in hex. For example, an HMAC-SHA256 Base64 signature converted to hex can be compared directly against OpenSSL command-line output or Wireshark captures.
What is Base64URL and how does the tool handle it?
Base64URL replaces + with - and / with _, and removes trailing = padding, making strings safe for JWT and URL parameters. The tool automatically detects - and _ characters, restores them to standard Base64, then decodes — no manual conversion needed.
What is the difference between the three output formats?
Plain hex outputs a continuous lowercase string (e3b0c4…), best for programmatic use. Spaced (e3 b0 c4) is easier to read and compare visually. The 0x format (0xe3, 0xb0, 0xc4) can be pasted directly into C, Go, or JavaScript byte array definitions.
Can I use the hex output with OpenSSL?
Yes. The command echo "47DEQpj8HBSa+/TImW+5JCeuQeRkm5NMpJWZG3hSuFU=" | base64 -d | xxd -p produces the same plain hex string as this tool's plain hex output.
Does the tool support Data URL input?
Yes. If you paste a Data URL like data:image/png;base64,iVBOR…, the tool strips the prefix, extracts the MIME type, and decodes the Base64 to hex bytes.
Will large Base64 inputs be slow?
The tool processes data in chunks to avoid stack overflow. In modern browsers, decoding Base64 under 10 MB typically completes in milliseconds. For very large files, consider using command-line tools (base64 -d | xxd) for better performance.