Format Viewer & Parser (FVP)
Your offline "Local-First" toolkit for every data format.
FVP is a complete workspace for developers: format, validate, compare, convert, and analyze many different data formats. Everything runs locally in your browser—no uploads, no tracking, no server required.
Messy data, made readable
Many tools. One workspace. Zero uploads.
What you can do
Make sense of data files, configs, and logs.
Whether you're reviewing API responses, checking deployment files, or cleaning up documentation, FVP gives you the tools to work faster.
Turn unreadable files into something you can actually review
Paste JSON from an API, a config file, or export—and see it formatted, indented, and color-coded instantly.
Compare two versions and see exactly what's different
Before deploying a config or merging changes, compare files side-by-side to catch additions, deletions, and modifications.
Preview Markdown and visualize flows without leaving your workspace
Write documentation or sketch system diagrams with live preview—export to HTML, PNG, or SVG when ready.
Find personal data and secrets before sharing files
Scan text for emails, phone numbers, API keys, and passwords—so you can remove them before posting to Slack or GitHub.
Validate Docker Compose, SQL schemas, and deployment files
Check syntax, visualize service relationships, and convert between formats—catch errors before they reach production.
Stop hunting through log files—see the entire request journey in one view
Paste logs from multiple services and watch FVP automatically connect the dots. See which service slowed down, where errors happened, and how long each step took—all in a visual timeline.
For developers
A technical toolkit with specialized format viewers.
Deep-dive into every format with validation, conversion, schema support, and advanced features.
Structured Data
JSON
Format, minify, validate, compare, tree view, JSONPath queries, and schema validation.
YAML
Parse and format YAML files with syntax validation and error reporting.
XML
Format and validate XML documents with proper indentation and error detection.
Universal Conversion
Convert between JSON, YAML, and XML formats seamlessly.
Encoding & Tokens
Base64
Encode and decode Base64, URL-safe Base64, and Data URLs.
JWT
Decode, validate, and analyze JSON Web Tokens with detailed claims inspection.
Docs & Diagrams
Markdown
Live preview with GitHub Flavored Markdown, code highlighting, and HTML export.
Mermaid
Render flowcharts, sequence diagrams, ERDs, Gantt charts, and more from text.
Advanced Tools
Protobuf
Decode and encode Protocol Buffers with schema validation and message inspection.
Log Tracer
Parse distributed traces from logs, visualize timelines, and analyze spans across services.
Docker Compose
Validate compose files, visualize service dependencies, and convert to Helm charts.
SQL Schema
Convert between SQL dialects and generate interactive ER diagrams from DDL.
PII & Secrets
Detect personal information and secrets with pattern matching and on-device AI.
On-device intelligence
Spot sensitive data with local AI—nothing leaves your machine.
FVP's PII & Secrets tool pairs fast pattern checks with an optional on-device model for trickier English, Arabic, and mixed text. Inference runs locally—no API keys and no uploads.
- Instant rules Emails, tokens, keys, and common secret patterns
- Private by design Scanning does not send your content to external services
Support This Project
Help keep FVP free to use
FVP is developed and maintained by Mohamed Sweelam. Your support helps cover development costs and keeps core features free.
FVP is and will always be free. Donations are entirely optional.