Base64 Tools Skill

Encode and decode data using Base64 encoding.

When to Use

✅ USE this skill when:

• "Encode this to base64"
• "Decode this base64"
• "Convert file to base64"
• "Decode base64 to file"
• "URL-safe base64 encoding"

When NOT to Use

❌ DON'T use this skill when:

• Cryptographic operations ΓåÆ use encryption tools
• Hash/generate signature ΓåÆ use hash-tools
• Compress data ΓåÆ use compression tools

Commands

Encode String

{baseDir}/base64.sh encode "Hello World"
{baseDir}/base64.sh encode "Hello World" --url-safe
{baseDir}/base64.sh encode --string "Hello World"

Decode String

{baseDir}/base64.sh decode "SGVsbG8gV29ybGQ="
{baseDir}/base64.sh decode "SGVsbG8gV29ybGQ" --url-safe
{baseDir}/base64.sh decode --string "SGVsbG8gV29ybGQ="

Encode File

{baseDir}/base64.sh encode --file image.png
{baseDir}/base64.sh encode --file document.pdf --output encoded.txt

Decode to File

{baseDir}/base64.sh decode --string "SGVsbG8gV29ybGQ=" --output output.txt
{baseDir}/base64.sh decode --file encoded.txt --output original.png

From Stdin

echo "Hello World" | {baseDir}/base64.sh encode
cat file.txt | {baseDir}/base64.sh encode --output encoded.txt

Check if Valid Base64

{baseDir}/base64.sh validate "SGVsbG8gV29ybGQ="
{baseDir}/base64.sh validate "not-valid-base64!"

Options

Option	Description	Default
--url-safe	Use URL-safe variant (-_ instead of +/)	false
--file FILE	Read from/write to file	stdin/stdout
--string STR	Direct string input	None
--output FILE	Output to file	stdout
--wrap COLS	Wrap encoded output at N columns	76
--no-wrap	Don't wrap encoded output	false
--ignore-garbage	Ignore non-base64 characters	false
--validate	Just validate, don't decode	false
--json	Output as JSON	false

URL-Safe Base64

Standard Base64 uses + and / which aren't URL-safe. The URL-safe variant replaces:

• + ΓåÆ -
• / ΓåÆ _
• Removes padding =

# Standard: SGVsbG8gV29ybGQ/==
# URL-safe: SGVsbG8gV29ybGQ_
{baseDir}/base64.sh encode "Hello?" --url-safe

Examples

Encode a string:

{baseDir}/base64.sh encode "Hello World"
# SGVsbG8gV29ybGQ=

Decode a string:

{baseDir}/base64.sh decode "SGVsbG8gV29ybGQ="
# Hello World

Encode a file:

{baseDir}/base64.sh encode --file image.png
# iVBORw0KGgoAAAANSUhEUgAA...

Decode to file:

{baseDir}/base64.sh decode --file encoded.txt --output image.png

URL-safe encoding:

{baseDir}/base64.sh encode "user@example.com" --url-safe
# dXNlckBleGFtcGxlLmNvbQ

Validate base64:

{baseDir}/base64.sh validate "SGVsbG8gV29ybGQ="
# Valid base64

JSON output:

{baseDir}/base64.sh encode "Hello" --json
# {"input": "Hello", "encoded": "SGVsbG8="}

Encode from stdin:

echo "secret data" | {baseDir}/base64.sh encode
# c2VjcmV0IGRhdGE=

Use Cases

Embed images in HTML/CSS:

ENCODED=$({baseDir}/base64.sh encode --file logo.png --no-wrap)
echo "background: url('data:image/png;base64,$ENCODED');"

Store binary in JSON:

# Encode binary file to base64, store in JSON field
{baseDir}/base64.sh encode --file binary.dat --json

API authentication:

# Create Basic Auth header
CREDS="user:pass"
ENCODED=$({baseDir}/base64.sh encode "$CREDS")
echo "Authorization: Basic $ENCODED"

Data URLs:

# Create data URL for image
{baseDir}/base64.sh encode --file icon.svg --output - | \
  sed 's/^/data:image\/svg+xml;base64,/'

Exit Codes

• 0: Success
• 1: Invalid base64 input (decode mode)
• 2: File not found
• 3: Permission denied

Notes

• Uses built-in base64 command (available on most systems)
• Wraps at 76 columns by default (MIME standard)
• Use --no-wrap for single-line output
• Binary files are handled correctly
• URL-safe encoding follows RFC 4648