# File Convert

> Convert between file formats: CSV↔JSON, Markdown↔HTML, YAML↔JSON, images, and more. No external service needed.

- Skill: `fuyuxiang/file-convert` (Agent Skill, multi-file: 2 files)
- Install (CLI): `npx skillmds@latest add fuyuxiang/file-convert`
- Raw SKILL.md: https://api.skillmd.com/api/skills/fuyuxiang/file-convert/raw
- Safety review: pending
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: Web & Frontend
- Author: fuyuxiang (https://skillmd.com/u/fuyuxiang)
- Updated: 2026-09-17
- Page: https://skillmd.com/skills/fuyuxiang/file-convert

---


# File Convert

Common format conversions using Python stdlib + minimal dependencies.

## Quick Conversions

### CSV → JSON
```bash
python3 -c "import csv,json,sys; print(json.dumps(list(csv.DictReader(open(sys.argv[1]))),ensure_ascii=False,indent=2))" data.csv
```

### JSON → CSV
```python
import json, csv, sys
data = json.load(open(sys.argv[1]))
w = csv.DictWriter(sys.stdout, fieldnames=data[0].keys())
w.writeheader(); w.writerows(data)
```

### YAML → JSON
```bash
python3 -c "import yaml,json,sys; print(json.dumps(yaml.safe_load(open(sys.argv[1])),ensure_ascii=False,indent=2))" file.yaml
```

### JSON → YAML
```bash
python3 -c "import yaml,json,sys; print(yaml.dump(json.load(open(sys.argv[1])),allow_unicode=True,default_flow_style=False))" file.json
```

### Markdown → HTML
```bash
pip install markdown
python3 -c "import markdown,sys; print(markdown.markdown(open(sys.argv[1]).read(),extensions=['tables','fenced_code']))" file.md
```

### Base64 encode/decode
```bash
base64 < file.bin > file.b64
base64 -d < file.b64 > file.bin
```

## Universal Converter Script

```bash
python3 scripts/convert.py input.csv output.json
python3 scripts/convert.py data.yaml data.json
python3 scripts/convert.py README.md README.html
```

Auto-detects format from file extension and performs the appropriate conversion.