Markdown to Portable Text Converter

Stop wasting 45 minutes per article on manual content migration. Convert ChatGPT, Claude, and Markdown files directly to Sanity's Portable Text format with one click.

markdown to portable text

Why Every Sanity User Needs This Converter

If you're creating content with AI tools like Claude or ChatGPT, you know they export everything as Markdown. But Sanity CMS uses Portable Text, a completely different format that requires complex JSON structures with blocks, spans, and marks.

The manual process is painful: Copy each paragraph individually. Reformat every heading. Fix broken links. Reconstruct code blocks. What should take 2 minutes takes 45. For teams publishing 20+ articles monthly, that's 15 hours of lost productivity.

Our free converter instantly transforms any Markdown content into perfectly formatted Portable Text JSON. Just paste, convert, and copy. Your content is ready for Sanity Studio or the Sanity API in seconds. No sign-up required, no data stored. Everything happens in your browser.

Convert Markdown to Portable Text

The Hidden Cost of Manual Markdown to Portable Text Migration

Every day, thousands of content teams waste hours converting Markdown to Portable Text. Here's why this seemingly simple task is destroying your content velocity:

The Complexity Gap Between Markdown and Portable Text

Markdown uses simple, human-readable syntax:

## My HeadingThis is a **bold** paragraph with a [link](https://example.com).

But Portable Text requires complex JSON structures:

[  {    "_key": "foefcw7rfbh",    "_type": "block",    "style": "h2",    "children": [      {        "_key": "z44no3ta8ib",        "_type": "span",        "text": "My Heading",        "marks": []      }    ],    "markDefs": []  },  {    "_key": "ig2bzv1hxg",    "_type": "block",    "style": "normal",    "markDefs": [      {        "_key": "m61v956m26kn",        "_type": "link",        "href": "https://example.com"      }    ],    "children": [      {        "_key": "qkfkh6qfsn",        "_type": "span",        "text": "This is a ",        "marks": []      },      {        "_key": "siv37r6hhsc",        "_type": "span",        "text": "bold",        "marks": [          "strong"        ]      },      {        "_key": "j2gk7g5b8bi",        "_type": "span",        "text": " paragraph with a ",        "marks": []      },      {        "_key": "30sw6nwy0o6",        "_type": "span",        "text": "link",        "marks": [          "m61v956m26kn"        ]      },      {        "_key": "14ajjim0h1o",        "_type": "span",        "text": ".",        "marks": []      }    ]  }]

Manual conversion means reconstructing this JSON structure by hand for every single element in your content.

Who's Losing Time to Manual Conversion?

Content Teams Using AI Writers

Marketing teams using Claude, ChatGPT, or Perplexity for content creation face a critical bottleneck. These AI tools only export Markdown, but Sanity needs Portable Text. Result: 30-45 minutes of reformatting per article.

Real Impact: A content team producing 20 articles/month loses 15 hours to migration, likely $2,000+ in monthly labor costs.

Technical Writers and Developer Advocates

Technical documentation lives in Markdown. GitHub READMEs, API docs, tutorials; They all use Markdown. But when your company blog runs on Sanity, every technical article requires painful manual conversion, especially for code blocks with syntax highlighting.

Real Impact: Developer advocates spend 20% of their time on content migration instead of content creation.

SEO Agencies and Content Studios

Agencies managing multiple Sanity installations waste countless billable hours on content migration. When you're publishing 50+ pieces monthly across clients, manual conversion becomes a significant operational burden.

Real Impact: Agencies report losing $5,000 - 10,000 monthly in billable hours to content migration tasks.

What Our Converter Handles Automatically

Complete Markdown Support

  • All Headers (H1-H6) - Maintains proper hierarchy
  • Rich Text Formatting - Bold, italic, strikethrough
  • Links - Both inline and reference-style
  • Lists - Ordered, unordered, and nested
  • Code Blocks - With language detection
  • Inline Code - Preserves backticks
  • Blockquotes - Proper quote formatting

Developer-Friendly Output

  • Valid JSON - Passes Sanity validation every time
  • Proper Keys - No duplicate key errors
  • Optimized Structure - Minimal nesting for performance
  • Clean Marks - Properly structured text annotations

How to Use Your Converted Content in Sanity

Method 1: Direct Studio Import

  1. Copy the generated Portable Text JSON
  2. In Sanity Studio, click the three-dot menu in any Portable Text field
  3. Select "Paste Portable Text"
  4. Paste and confirm

Method 2: API Integration

import {createClient} from '@sanity/client'const client = createClient({  projectId: 'your-project-id',  dataset: 'production',  token: 'your-token'})// Portable Text from our converterconst convertedContent = [/* ... */]await client.create({  _type: 'post',  title: 'Your Article',  content: convertedContent})

Method 3: Bulk Import (Coming Soon)

Our upcoming bulk converter will handle entire folders of Markdown files, maintaining internal links and metadata.

Common Conversion Challenges We've Solved

Code Block Language Detection

  • Problem: Markdown often lacks language specifications
  • Our Solution: Intelligent syntax-based language detection

Nested List Structures

  • Problem: Complex nesting breaks most converters
  • Our Solution: Recursive parsing maintains full hierarchy

Mixed Inline Formatting

  • Problem: Combined bold, italic, and links confuse parsers
  • Our Solution: Proper mark stacking preserves all formatting

GitHub Flavored Markdown

  • Problem: GFM extensions aren't standard
  • Our Solution: Configurable parser handles multiple flavors

What's Coming Next: Bulk Migration Tools

While our free converter handles individual documents perfectly, we're building enterprise features for power users:

Bulk Converter (Q1 2026)

  • Convert entire documentation repositories
  • Maintain cross-document links
  • Preserve frontmatter and metadata
  • Direct Sanity dataset upload
  • CSV mapping for structured content

Custom Block Mapping

  • Map Markdown patterns to custom Portable Text blocks
  • Support for company-specific components
  • Preserve special annotations
  • Team formatting standards

AI Enhancement Layer

  • Automatic SEO optimization during conversion
  • Smart alt text generation
  • Content structure validation
  • Readability improvements

Why ContentWrap's Converter Is Different

Built by Migration Experts

We've migrated over 10,000 documents to Sanity, including enterprise documentation systems, multi-language content, and complex technical wikis. Every edge case is handled.

Privacy-First Design

  • No server storage - Conversion happens in your browser
  • No tracking - We don't analyze your content
  • No sign-up - Start converting immediately
  • Open core - Audit our conversion logic

Enterprise-Ready Output

  • Validates against Sanity's schema requirements
  • Handles special characters and Unicode
  • Preserves document structure
  • Maintains content relationships

Frequently Asked Questions