HTML Preview

HTML Live Preview — Run HTML, CSS & JS Online

Write HTML and see it rendered live — no install, no signup.

HTML Editor

<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8" />
  <meta name="viewport" content="width=device-width, initial-scale=1.0" />
  <title>TinyTools — HTML Preview</title>
  <style>
    /* TinyTools brand palette */
    :root {
      --primary:   #f97316;
      --primary-dark: #ea580c;
      --accent:    #fbbf24;
      --bg:        #fafafa;
      --surface:   #ffffff;
      --text:      #1e293b;
      --muted:     #64748b;
      --border:    #e2e8f0;
      --radius:    12px;
    }

* { box-sizing: border-box; margin: 0; padding: 0; }

body {
      font-family: 'Inter', 'Segoe UI', sans-serif;
      background: var(--bg);
      color: var(--text);
      padding: 32px 24px;
      min-height: 100vh;
    }

.header {
      display: flex;
      align-items: center;
      gap: 14px;
      margin-bottom: 32px;
    }

.logo {
      width: 44px;
      height: 44px;
      border-radius: 10px;
      background: linear-gradient(135deg, var(--primary), var(--accent));
      display: flex;
      align-items: center;
      justify-content: center;
      font-size: 22px;
      font-weight: 800;
      color: white;
      letter-spacing: -1px;
      flex-shrink: 0;
    }

.brand-name {
      font-size: 20px;
      font-weight: 700;
      color: var(--text);
    }

.brand-tagline {
      font-size: 13px;
      color: var(--muted);
      margin-top: 2px;
    }

.hero {
      background: linear-gradient(135deg, var(--primary) 0%, var(--accent) 100%);
      border-radius: var(--radius);
      padding: 36px 32px;
      color: white;
      margin-bottom: 28px;
      position: relative;
      overflow: hidden;
    }

.hero::before {
      content: '';
      position: absolute;
      top: -40px; right: -40px;
      width: 180px; height: 180px;
      border-radius: 50%;
      background: rgba(255,255,255,0.08);
    }

.hero h1 {
      font-size: 28px;
      font-weight: 800;
      margin-bottom: 10px;
      position: relative;
    }

.hero p {
      font-size: 15px;
      opacity: 0.9;
      max-width: 480px;
      line-height: 1.6;
      position: relative;
    }

.badge {
      display: inline-block;
      background: rgba(255,255,255,0.2);
      color: white;
      font-size: 12px;
      font-weight: 600;
      padding: 4px 12px;
      border-radius: 999px;
      margin-bottom: 14px;
    }

.cards {
      display: grid;
      grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
      gap: 16px;
      margin-bottom: 28px;
    }

.card {
      background: var(--surface);
      border: 1px solid var(--border);
      border-radius: var(--radius);
      padding: 20px;
      box-shadow: 0 2px 8px rgba(0,0,0,0.05);
      transition: transform 0.2s, box-shadow 0.2s;
    }

.card:hover {
      transform: translateY(-2px);
      box-shadow: 0 6px 20px rgba(249,115,22,0.12);
    }

.card-icon {
      width: 36px;
      height: 36px;
      border-radius: 8px;
      background: linear-gradient(135deg, var(--primary), var(--accent));
      display: flex;
      align-items: center;
      justify-content: center;
      font-size: 18px;
      margin-bottom: 12px;
    }

.card h3 {
      font-size: 15px;
      font-weight: 600;
      margin-bottom: 6px;
      color: var(--text);
    }

.card p {
      font-size: 13px;
      color: var(--muted);
      line-height: 1.5;
    }

.cta {
      display: flex;
      align-items: center;
      gap: 12px;
      padding: 16px 20px;
      background: var(--surface);
      border: 1px solid var(--border);
      border-radius: var(--radius);
      margin-top: 8px;
    }

.cta-text {
      flex: 1;
      font-size: 14px;
      color: var(--muted);
    }

.btn {
      background: linear-gradient(135deg, var(--primary), var(--accent));
      color: white;
      border: none;
      padding: 10px 22px;
      border-radius: 8px;
      font-size: 14px;
      font-weight: 600;
      cursor: pointer;
      transition: opacity 0.2s;
    }

.btn:hover { opacity: 0.88; }
  </style>
</head>
<body>
  <header class="header">
    <div class="logo">T</div>
    <div>
      <div class="brand-name">TinyTools</div>
      <div class="brand-tagline">Free Browser Tools — No Signup</div>
    </div>
  </header>

<section class="hero">
    <span class="badge">HTML Preview Tool</span>
    <h1>Edit HTML. See it live.</h1>
    <p>
      Write any HTML, CSS or JavaScript on the left panel and watch it
      render instantly here — powered by TinyTools HTML Preview.
    </p>
  </section>

<div class="cards">
    <div class="card">
      <div class="card-icon">⚡</div>
      <h3>Instant Preview</h3>
      <p>Changes reflect in real-time as you type — no refresh needed.</p>
    </div>
    <div class="card">
      <div class="card-icon">🔒</div>
      <h3>Sandboxed &amp; Safe</h3>
      <p>Your code runs in an isolated iframe — completely secure.</p>
    </div>
    <div class="card">
      <div class="card-icon">📐</div>
      <h3>Fullscreen Mode</h3>
      <p>Expand the preview to full screen for a distraction-free view.</p>
    </div>
    <div class="card">
      <div class="card-icon">🛠️</div>
      <h3>No Signup</h3>
      <p>100% free and browser-based. Your code never leaves your device.</p>
    </div>
  </div>

<div class="cta">
    <p class="cta-text">Explore 100+ free tools at <strong>tinytools.in</strong></p>
    <button class="btn" onclick="window.open('https://tinytools.in','_blank')">
      Visit TinyTools
    </button>
  </div>
</body>
</html>

5,529 chars · 236 lines

Live Preview

Source

Rendered Preview

Supports full HTML5 including inline CSS and JavaScript. Your code runs in a sandboxed iframe — nothing is sent to our servers.

Was this tool helpful?Your feedback helps us make TinyTools better

Quick Start Instructions

Write or paste HTML, CSS, and JS to see a live sandboxed render on the right. Switch to Source view, copy output, or go fullscreen. Zero data collection.

1Paste or type your raw HTML, inline CSS, or JavaScript into the left editor pane.
2Observe the rendered web page update automatically in the right Live Preview window.
3Toggle to the Source tab to verify cleanly formatted HTML output code.
4Click the Fullscreen button to test responsive page layouts across standard monitor sizes.
5Click Copy HTML to export your finalized code directly to your clipboard.

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Frequently Asked Questions

How does the live HTML Preview tool work?

The TinyTools HTML Preview renders code in real time using a client-side sandboxed iframe (srcdoc attribute). As you type or paste HTML, CSS, and JavaScript in the left editor, the browser dynamically renders the visual output on the right instantly without sending any data to remote servers.

Is this online HTML preview safe for untrusted or custom code?

Yes. The preview environment enforces HTML5 iframe sandboxing (sandbox='allow-scripts allow-same-origin allow-forms allow-modals'). This restricts malicious script access to host cookies, localStorage, and parent window objects while allowing CSS, animations, and scripts to execute safely.

Can I preview HTML email templates and inline CSS styles?

Yes. The previewer supports full HTML email markup including inline CSS, HTML tables, embedded media, and web fonts. It allows developers and email marketers to verify layout responsiveness before sending newsletters.

Does this tool support JavaScript, external CSS libraries, and CDN scripts?

Yes. You can include external scripts and stylesheets (e.g., Tailwind, Bootstrap, FontAwesome, Google Fonts) via standard <link> and <script> tags. Inline JavaScript functions and DOM manipulation work seamlessly within the sandbox.

Is my HTML code uploaded or stored on any server?

No. All parsing and execution occur 100% locally inside your web browser. TinyTools never sends, logs, or stores your source code or input data on any external server.

How do I switch to full screen mode for visual inspection?

Click the Fullscreen button located in the top right corner of the preview panel. This expands the render container to fill your viewport, giving you an uncluttered full-page view of your web page or UI component.

Detailed Guide & Overview

What is the TinyTools Online HTML Previewer?

The TinyTools HTML Preview tool is a free, zero-latency browser-based application that allows developers, designers, and content creators to write, edit, and instantly visualize raw HTML, CSS, and JavaScript code in real time. Featuring client-side sandboxed execution, fullscreen testing, and zero-server logging, it provides a safe environment for prototyping web components, inspecting email templates, and testing code snippets.

HTML Preview Tool Technical Specifications

Feature	Specification / Capability
Execution Engine	Client-Side Browser DOM Engine (Chromium / Firefox / Safari)
Sandbox Isolation	`<iframe srcdoc>` with restricted sandbox attributes
Supported Technologies	HTML5, CSS3 (Flexbox/Grid), JavaScript ES6+, External CDN Assets
Privacy & Security	100% In-Browser Execution. No network uploads or server logging
Display Modes	Side-by-side split view, Raw Source Viewer, Fullscreen Mode

Primary Use Cases for Online HTML Rendering

An online HTML previewer is an indispensable tool across modern web workflows:

HTML Email Template Testing: Preview marketing emails, newsletter tables, and inline CSS styles across simulated viewports to fix layout shifts before sending campaigns.
Rapid UI Component Prototyping: Test buttons, card layouts, modal dialogs, and navigation bars quickly without setting up a full local web server or bundler.
Education & Code Learning: Experiment with fundamental web markup, tag syntax, CSS flexbox properties, and DOM event listeners with zero setup cost.
CMS & Blog Content Inspection: Verify HTML snippets, embedded embeds, and formatted content before publishing them to platforms like WordPress, Ghost, or Shopify.
Cross-Browser CSS Debugging: Isolate complex CSS rule sets and inspect CSS variable inheritance in real time.

How In-Browser Security & Sandboxing Safeguards Your Environment

Security is a core priority when previewing arbitrary code. TinyTools uses modern web standards to ensure safety:

The preview engine renders your raw code inside a sandboxed <iframe> using the native srcdoc attribute. By setting strict sandbox="allow-scripts allow-same-origin allow-forms allow-modals" directives:

Scripts can run interactive logic within the isolated preview window.
Code inside the preview is blocked from reading or mutating host site cookies, session tokens, or localStorage.
Dangerous top-level navigation, automatic popups, and unauthorized file downloads are prevented by browser policy.
Your code execution remains strictly contained within your browser's local client memory.

Step-by-Step Guide: How to Preview HTML Code Instantly

Input Your Code: Enter or paste your raw HTML5 markup, <style> tags, or <script> blocks into the left editor pane.
Instant Live Rendering: As you modify characters, the live renderer updates the preview window on the right side without requiring page reloads.
Inspect Formatted Source: Switch between the Live Preview and Source tabs to review raw HTML tags or copy formatted code directly.
Full Viewport Testing: Click the Fullscreen icon to expand the preview panel, allowing you to test responsiveness across desktop viewport sizes.
Export Your Work: Use the Copy button to capture your finalized code to your clipboard for instant deployment into your project.

Comparing HTML Preview vs. Markdown Converters

While both tools assist with content presentation, they fulfill different technical needs:

HTML Preview: Accepts direct HTML5 code, embedded stylesheets, and JavaScript logic. Provides granular control over CSS layout, custom tags, and DOM events.
Markdown to HTML Converter: Accepts lightweight Markdown syntax (like # Heading or **bold**) and transforms it into standard semantic HTML elements for documentation and blogging.