How do I decode a Base64 string online?

Paste your Base64 string into SmartDevBox at smartdevbox.com. It automatically detects Base64 encoding and decodes it instantly — no configuration needed.

How do I decode a JWT token without a secret?

Paste your JWT token into SmartDevBox. The JWT Inspector tool decodes the header and payload and displays them as readable JSON. Note: this decodes but does not verify the signature — you don't need the secret to read the claims.

How do I format or pretty-print JSON?

Paste your minified or unformatted JSON into SmartDevBox. The JSON Formatter tool detects it automatically and pretty-prints it with configurable indentation.

How do I convert a Unix timestamp to a human-readable date?

Paste a Unix timestamp (e.g. 1700000000) into SmartDevBox. The Unix Timestamp converter detects it and shows the equivalent date and time in UTC and your local timezone.

How do I convert JSON to CSV?

Paste a JSON array of objects into SmartDevBox and select the JSON → CSV tool. It converts your data to comma-separated format with headers derived from the JSON keys.

How do I compute a SHA-256 hash online?

Use the Hash Generator tool on SmartDevBox. Paste any text and it computes MD5, SHA-1, SHA-256, and SHA-512 hashes simultaneously in the browser.

How do I parse and understand a cron expression?

Paste your cron expression (e.g. "0 9 * * 1-5") into SmartDevBox. The Cron Job Parser explains it in plain English and shows the next scheduled run times.

How do I decode an X.509 certificate online?

Paste a PEM-encoded certificate (beginning with -----BEGIN CERTIFICATE-----) into SmartDevBox. The Certificate Decoder extracts and displays the subject, issuer, validity dates, public key, and extensions.

Is SmartDevBox free to use?

Yes. SmartDevBox is completely free with no account or sign-up required. All tools run in the browser. An optional AI mode (for ambiguous input detection) can be enabled with your own OpenAI API key.

Does SmartDevBox send my data to a server?

No. All tools run entirely in the browser using client-side JavaScript. Your data never leaves your machine unless you opt into the AI mode, which sends input to OpenAI for format detection.

What is the best free online JSON formatter?

SmartDevBox automatically detects JSON when you paste it and formats it with configurable indentation. It also validates JSON and reports syntax errors with precise line and column numbers — all in the browser, free, with no account required.

What is the best free online Base64 decoder?

SmartDevBox auto-detects Base64 strings — including standard and URL-safe variants, with or without padding — and decodes them instantly on paste. No button to click, no tool to select.

How do I compare two JSON objects online?

Use the Split & Diff tool in SmartDevBox. Paste the first JSON in the left pane and the second in the right pane. Changes are highlighted line-by-line in real time.

Can I add my own tools to SmartDevBox?

Yes. SmartDevBox has a plugin system that lets developers register custom tools by providing a name, a detector function (returns a confidence score 0–1), and a transformer function. Custom tools appear in the sidebar alongside the 91 built-in tools and participate in auto-detection.

Does SmartDevBox work offline?

SmartDevBox is a Progressive Web App (PWA). All 91 tools run entirely client-side with no server dependency. Once the page is loaded, the tools work without an internet connection. AI mode requires connectivity.

Glossary

What Is a Color Code?

A color code is a notation that tells a computer exactly which color to display. CSS supports several formats — HEX, RGB, HSL, and their alpha-channel variants — each suited to different workflows. Designers often prefer HSL for its human-intuitive hue/saturation/lightness model; engineers reach for HEX because it is compact and universally recognised.

The One-Line Definition

A color code is a standardised notation — HEX, RGB, HSL, or a named keyword — that uniquely identifies a color so browsers, design tools, and image processing libraries all render the same value.

Color Code Formats

HEX — #FF5733Range: 00–FF per channel
Most compact. 3-char shorthand (#RGB) for doubles: #ABC = #AABBCC.

HEXA — #FF573380Range: 00–FF per channel + alpha
8-digit HEX adds an alpha channel. Less widely supported than rgba().

RGB — rgb(255, 87, 51)Range: 0–255 per channel
Additive model. All channels at 255 = white; all at 0 = black.

RGBA — rgba(255, 87, 51, 0.5)Range: 0–255 + alpha 0–1
Alpha 0 = fully transparent; 1 = fully opaque.

HSL — hsl(11, 100%, 60%)Range: H:0–360°, S:0–100%, L:0–100%
H=hue angle, S=saturation, L=lightness. Intuitive for design adjustments.

HSLA — hsla(11, 100%, 60%, 0.5)Range: HSL + alpha 0–1
Same as HSL with an alpha channel for transparency.

How to Convert HEX to RGB

1. Strip the #Remove the leading hash character from the 6-digit string.

2. Split into pairsTake the first 2 chars as red, next 2 as green, last 2 as blue.

3. Parse base 16Convert each hex pair to decimal. FF → 255, 00 → 0, 80 → 128.

4. Compose rgb()Wrap in rgb(R, G, B). Example: #1A2B3C → rgb(26, 43, 60).

Why HSL Is Useful

Lighten a colorIncrease L (lightness). hsl(200, 80%, 40%) → hsl(200, 80%, 60%).

Darken a colorDecrease L. hsl(200, 80%, 60%) → hsl(200, 80%, 30%).

Desaturate (grey out)Decrease S. hsl(200, 80%, 50%) → hsl(200, 10%, 50%).

Create a complementary colorAdd 180° to H. hsl(30, …) → hsl(210, …).

Create a triadic paletteAdd 120° increments: H, H+120, H+240.

Add transparencySwitch to hsla() and set alpha < 1.

Convert Color Codes Now

Color Converter → — convert HEX ↔ RGB ↔ HSL instantly in the browser.

Frequently Asked Questions

What is a HEX color code?

A 6-digit hexadecimal string prefixed with #. Each pair represents a color channel (RR, GG, BB) on a 0–255 scale in base 16. #FF5733 = red=255, green=87, blue=51.

What is the difference between RGB and HSL?

RGB specifies red/green/blue channel intensities (0–255). HSL specifies hue (0–360°), saturation (0–100%), and lightness (0–100%). HSL is more intuitive for design: increase L to lighten, decrease S to grey out.

What does the A in RGBA and HSLA mean?

Alpha — the opacity channel. 0 is fully transparent, 1 is fully opaque, 0.5 is 50% transparent.

How do I convert HEX to RGB online?

Paste the HEX value into the SmartDevBox Color Converter. It outputs the RGB and HSL equivalents instantly, all client-side.

Color Converter →Convert HEX, RGB, and HSL color codes in the browser.

What Is Base64? →Base64 is used to encode binary image data — including colors — as text.

What Is JSON? →JSON is often used to store theme tokens including color codes in design systems.