Have you ever needed to format a production SQL query containing customer records, parse a cURL command with an active Authorization: Bearer secret, or convert sensitive JSON data to TypeScript types?
Most online formatters and conversion tools send your clipboard content to remote backend servers. If their servers are compromised, log incoming requests, or use third-party analytics, your internal tokens and database schemas are exposed.
To solve this, Digital Vault PRO is an open, client-side utility suite built on Astro 5, WebAssembly, and the Web Crypto API. 100% of calculations execute locally in your browser ā zero bytes are ever uploaded to any server.
Here are 10 of the most practical tools available for daily engineering workflows:
1. cURL to Code Converter
Quickly transform complex curl requests with headers, multi-line arguments, and JSON payloads into clean, idiomatic code for:
- JavaScript
fetch()(async/await) - Python
requests - Go
http.NewRequest - PHP
curl_init
It parses quotes and multi-line arguments locally without sending your auth headers across the wire.
2. Docker Run to Docker Compose Converter
Paste one or multiple docker run -d --name app -p 8080:80 -v /data:/var/www -e ENV=prod nginx:alpine commands and instantly generate a standardized docker-compose.yml file with port mappings, volume definitions, environment arrays, and restart policies.
3. JSON to TypeScript Interface Generator
Paste raw API responses or nested JSON objects. The engine infers types, generates clean PascalCase TypeScript interfaces, detects optional properties, and handles recursive structures.
4. CSV to SQL INSERT Query Generator
Convert spreadsheet CSV exports into batch INSERT INTO table (...) VALUES (...) statements:
- Automatically infers integers, floating-point numbers, booleans, and SQL
NULL - Escapes special characters
- Supports PostgreSQL, MySQL, and MS SQL dialects in batches of 50 rows
5. Linux Chmod Permissions Calculator
Visual matrix toggles for Read (r), Write (w), and Execute (x) permissions across Owner, Group, and Public tiers. Generates octal numbers (e.g., 755, 644) and symbolic strings (rwxr-xr-x) on the fly.
6. IPv4 CIDR Subnet Calculator
Calculate network address, broadcast address, netmask, wildcard mask, usable host IP ranges, and total address counts for subnets ranging from /1 to /32.
7. Client-Side Diff Checker
Side-by-side and inline syntax difference viewer using Myers diff algorithm. Compare source code, configuration files, and SQL schemas with zero server involvement.
8. Visual Cron Expression Generator
Visually configure cron intervals (minute, hour, day, month, weekday), view human-readable explanations in plain English, and calculate the next 5 execution timestamps.
9. Aspect Ratio & Resolution Calculator
Compute greatest common divisors (GCD), identify standard aspect ratios (16:9, 4:3, 21:9, 9:16), and scale dimensions without distorting images or videos.
10. Client-Side Word & Keyword Frequency Analyzer
Analyze texts and markdown articles: unigrams, bigrams, trigrams, reading time, character counts, and keyword density ā ideal for SEO and documentation polish.
Privacy and Self-Hosting
- Live web app: vault-pro.rashid-salimov96.workers.dev
-
Bilingual: English & Russian (
/en/and/) - Self-hosting: The entire project can be hosted locally via an Alpine Nginx Docker container (~15MB) with zero cloud dependencies.
Bookmark it, keep your API secrets safe, and let me know in the comments which developer utility you would like to see added next!
Top comments (4)
The chmod calculator is the one for me! Iām learning Linux and I still have to stop and think every time I see 755 or 644 š Being able to toggle it visually and see the octal and rwx side by side makes it click so much faster. Bookmarked!
Glad it helped! Honestly even after years of using Linux, almost everyone still double-checks SSH keys (
chmod 600 ~/.ssh/id_rsavs644for.puband700for~/.ssh) to avoid permission denied headaches.Seeing the binary bitmask (4 for read, 2 for write, 1 for execute) mapped directly to the checkboxes makes it much less abstract when you're starting out.
Thanks for the extra tip Rashid! Great post
Glad it helped, Maame! Octal permissions definitely take a while to become second nature, especially when you encounter sticky bits or setuid (4755 vs 0755). Having the interactive checkboxes map directly to the 3-digit octal notation makes the mental model click so much faster. Happy hacking with Linux!