dt — Developer Toolkit

Terminal Swiss Army Knife
UUID · Base64 · Color Converter · JWT Decoder · SHA Hash · JSON · QR Code · Password Generator · CIDR · MAC · Image Metadata — all in one command.

No more leaving your terminal to copy-paste into online tools.

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Features

Zero setup	Install once, use anywhere with the dt command
Interactive mode	Run dt with no args for a categorized menu — great for beginners
Search mode	Press s or / in interactive mode to search commands by name, alias, or description
Number shortcuts	Select commands by number in interactive mode; also supports command names and aliases directly
Pipe friendly	echo "hello" | dt base64 encode — works with Unix pipelines
JSON output	Add --json for machine-readable output, pipeable to jq
Clipboard copy	Press C in interactive mode to copy results to clipboard
Beautiful output	Colorful, well-formatted results with chalk and categorized display
Minimal deps	Only depends on chalk and qrcode — everything else uses Node.js built-in APIs

Install

# Install globally
npm install -g devkits

# Or use directly without installing
npx devkits

Usage

dt <command> [options]

Run without arguments for interactive mode:

dt

Get help for any command:

dt help               # Show main help (grouped by category)
dt help uuid          # Show help for a specific command
dt uuid --help        # Same as above

Commands (by category)

Security & Crypto

Command	Alias	Description
jwt	—	Decode or encode JWT tokens with expiry detection & HMAC verification
hash	—	Generate hashes (SHA family, MD5, BLAKE2, CRC32) & HMAC

Encoding

Command	Alias	Description
base64	—	Encode or decode Base64 (standard & URL-safe)
url	—	Encode, decode, or parse URLs & query strings

Network

Command	Alias	Description
cidr	—	CIDR/IP calculator (network, broadcast, subnet mask, host range)
mac	—	Format and validate MAC addresses (colon/hyphen/dot/cisco/unix)
ip	—	Look up IP address information & geolocation

Data Processing

Command	Alias	Description
json	—	Format, validate, and highlight JSON
diff	—	Compare two strings or files
csv	—	Format and view CSV data
ascii	—	ASCII / character lookup table
case	—	Convert strings between casing formats
regex	—	Test regex patterns & show matches with capture groups
text	—	Text stats & transformations (wc, reverse, slug, word frequency)

Utilities

Command	Alias	Description
uuid	—	Generate UUIDs (v1/v4/v7)
color	—	Convert colors (HEX / RGB(A) / HSL(A) / named)
timestamp	ts	Convert between Unix timestamps and dates
qrcode	qr	Generate QR codes in the terminal
random	rand	Generate passwords & random numbers
bytes	—	Convert byte sizes (B, KB, MB, GB, TB, PB)
completion	—	Generate shell auto-completion scripts
cron	—	Parse and describe cron expressions
lorem	—	Generate Lorem ipsum placeholder text
semver	sv	Parse, validate, compare, and bump semver
fake	—	Generate fake data (names, emails, IPs, companies & more)

Mathematics

Command	Alias	Description
math	—	Evaluate mathematical expressions
number	num	Convert between decimal, hex, binary, octal

Media

Command	Alias	Description
image	—	Show image file metadata (PNG, JPEG, GIF, WebP)

All commands support --json for structured JSON output.

Examples

Base64

dt base64 encode "hello world"
dt base64 decode "aGVsbG8gd29ybGQ="
echo "hello" | dt base64 encode
dt base64 encode "hello" --json # → {"action":"encode","input":"hello","output":"aGVsbG8="}
dt base64 encode "hello" --url  # URL-safe (no padding)

Color Converter

dt color "#ff7f50"
dt color "rgb(255, 127, 80)"
dt color "hsl(16, 100%, 66%)"
dt color coral
dt color coral --json           # → {"hex":"#FF7F50","rgb":"rgb(255,127,80)","hsl":"hsl(16,100%,66%)"}
dt color "#ff7f5080"             # RGBA with alpha

JWT

dt jwt "eyJhbGciOiJIUzI1NiJ9.eyJuYW1lIjoiSm9obiJ9.xxx"
dt jwt <token> --json           # → {"header":{...},"payload":{...},"expired":true/false}
dt jwt <token> --verify secret  # Verify HMAC signature
dt jwt encode '{"name":"John"}' --secret mysecret   # Create a signed token
dt jwt encode name=John role=admin --exp 3600         # key=value payload + expiry
dt jwt encode '{"sub":"123"}' --no-sign             # Unsigned token

Hash

dt hash "hello"
dt hash "hello" --algo sha512
dt hash "hello" -a sha512       # Same as --algo sha512
dt hash "hello" --algo md5
dt hash "hello" --algo crc32
dt hash "hello" --algo sha3-256 --format base64
echo "hello" | dt hash
dt hash "hello" --json          # → {"algorithm":"SHA256","input":"hello","hash":"2cf2..."}
dt hash --file config.json       # Hash file contents
dt hash "hello" --key secret     # HMAC-SHA256

Timestamp / ts

dt ts                         # Current timestamp
dt ts 1716806400              # Timestamp → readable date
dt ts "2026-05-28"            # Date → timestamp
dt ts 1716806400 --utc        # UTC time
dt ts 1716806400 --iso        # ISO 8601 format
dt ts now --json              # → {"unix":...,"iso":"...","local":"...","utc":"..."}
echo 1716806400 | dt ts       # Pipe input
dt ts now --timezone Asia/Shanghai  # Show time in specific timezone

JSON

dt json '{"a":1,"b":{"c":2}}'
echo '{"a":1}' | dt json
dt json '{"a":1}' --minify   # {"a":1}
dt json "invalid" --validate # Check validity

QR Code

dt qrcode "https://example.com"
echo "hello" | dt qrcode

Random

dt random password                    # 16-char password
dt random password -l 32 --no-symbols # 32-char alphanumeric
dt random number --min 1 --max 10     # Random integer
dt random password -c 5               # 5 passwords at once

Regex

dt regex "\\d+" "order 42 item 7" --flags g   # Show all matches
dt regex "(\\w+)@(\\w+)" "a@b.com c@d.io"   # Capture groups
dt regex "\\s+" "a  b   c" --replace "-"     # Preview replacement
echo "abc123" | dt regex "[a-z]+" --flags g --json

Text

dt text "hello world"              # Stats: words, chars, lines, bytes…
cat file.txt | dt text             # wc-style counting via pipe
dt text "My Project Name" --slug   # → my-project-name
dt text "hello world" --reverse    # → dlrow olleh
dt text "foo bar foo" --freq       # Word frequency table
dt text "b\na\nc" --sort --unique   # Line operations

Fake Data

dt fake name                        # Random full name
dt fake email                       # Random email address
dt fake -c 5 ip                     # 5 random IPs
dt fake integer --min 1 --max 10    # Random integer
dt fake password --json             # JSON output

URL

dt url encode "hello world"           # → hello%20world
dt url decode "hello%20world"         # → hello world
dt url parse "?foo=1&bar=2"           # Parse query string
echo "hello world" | dt url encode

CIDR

dt cidr 192.168.1.0/24          # Show network info
dt cidr 10.0.0.0/8             # Class A network

Math

dt math "sqrt(16) * 3"          # 12
dt math "2^10"                  # 1024
dt math "sin(PI/2)"             # 1
dt math "100 / 3" --precision 4 # 33.3333

MAC Address

dt mac aa:bb:cc:dd:ee:ff
dt mac AA-BB-CC-DD-EE-FF        # Auto-detects format
dt mac aabb.ccdd.eeff            # Also valid

Diff

dt diff "abc" "abd"
dt diff --file old.txt new.txt

CSV

echo "a,b,c\n1,2,3" | dt csv
dt csv "name,age\nAlice,30"

Image

dt image screenshot.png          # Show PNG metadata
dt image photo.jpg               # Show JPEG metadata

IP

dt ip                           # Your public IP & location
dt ip 8.8.8.8                   # Look up a specific IP

Development

git clone https://github.com/yvng-jie/devtools-cli.git
cd devtools-cli
pnpm install

pnpm dev <command>   # Run in dev mode (e.g. pnpm dev uuid)
pnpm build           # Production build → dist/
pnpm test            # Run tests (vitest)
pnpm lint            # Check code style
pnpm typecheck       # TypeScript type check

Contributing

PRs and issues are welcome! See CONTRIBUTING.md for guidelines.

License

MIT © yvng-jie