43 free tools live · zero uploads · browser-only

Free file conversion tools: Excel, CSV, XML, JSON and ZIP.

43 file conversion and dev utility tools running entirely in your browser. Convert between Excel, CSV, XML and JSON, format JSON, hash and encode text, generate QR codes, barcodes and favicons, with zero uploads and no account.

  • Files never leave your device
  • No account needed
  • Free to use

The catalog

43 file conversion tools, grouped by task

Pick a category below, then a tool.

Dev Utilities

Handy tools for developers

JSON, Base64, hashing, UUIDs, passwords, regex and more.

JSON Formatter / Validator

Pretty-print, minify, and validate JSON.

Base64 Encoder/Decoder

Encode text to Base64, or decode Base64 back to text.

Hash Generator (MD5/SHA-256)

Generate an MD5 or SHA-256 hash from text or a file.

UUID Generator

Generate one or more random UUIDs (v4).

Password Generator

Generate a strong, random password.

Regex Tester

Test a regular expression against sample text.

URL Encoder/Decoder

Encode or decode text for safe use in a URL.

Markdown ↔ HTML Converter

Convert Markdown to HTML, or HTML back to Markdown.

JWT Decoder

Decode a JSON Web Token to view its header and payload.

Meta Tag Generator

Generate title, description, Open Graph, and Twitter Card meta tags.

Cron Expression Builder

Build and understand cron expressions with a plain-English explanation.

HTML Entity Encoder / Decoder

Encode text to HTML entities or decode entities back to text.

Subnet Calculator

Calculate network address, broadcast address, and host range from CIDR.

URL Parser

Break a URL down into its protocol, host, path, and query parameters.

Number Base Converter

Convert numbers between binary, octal, decimal, and hexadecimal.

Roman Numeral Converter

Convert between Roman numerals and regular numbers, both directions.

GCD / LCM Calculator

Find the greatest common divisor and least common multiple of numbers.

Prime Number Checker

Check if a number is prime and see its prime factorization.

Quadratic Equation Solver

Solve ax squared plus bx plus c equals 0 for real or complex roots.

Ohm's Law Calculator

Calculate voltage, current, resistance, or power from any two values.

Why use it

Built the same way as every other Slaytic tool

  1. 01

    100% private

    Every tool processes your file using JavaScript inside your browser tab. Nothing is ever uploaded to a server.

  2. 02

    Instant results

    No upload wait, no queue. Processing runs on your own device and finishes in seconds.

  3. 03

    Always free

    No account, no trial, no limits. Every file conversion tool is free to use without restriction.

Questions

Before you dive in

Are all these file conversion tools free?

Yes. All 27 tools are completely free with no limits, no premium tier, and no account required.

Do my files get uploaded to a server?

No. Every tool uses SheetJS, Papa Parse, JSZip, or the native browser DOM API, all running entirely in your browser. Your files never leave your device.

How do I convert CSV to Excel for free?

Open the CSV to Excel tool, drop your CSV file, and click Convert. SheetJS processes it in your browser and your Excel file downloads instantly.

Is there a file size limit?

No enforced limit. Very large files may process more slowly since everything runs locally on your device.

Open a tool and get started.

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