Access Free Tools

Home / Categories

Free Developer Tools

Use developer tools for fast technical checks without opening a heavyweight app. The goal is simple: make encoding, formatting, subnetting, passwords, URLs, and debugging helpers easy to run in the browser with clear privacy notes.

Fast technical checks in the browser

Developer tools should be copy-friendly, private by default, and clear about security assumptions. They are useful for routine checks, not a substitute for production review.

I need network ranges Calculate CIDR ranges, usable hosts, masks, broadcast addresses, and network blocks. I need a password Generate strong random passwords and review length, symbols, and storage advice. I need URL encoding Percent-encode or decode URL component text without sending it away. I need readable JSON Format, validate, and copy JSON while keeping the source text in the browser. I need campaign URLs Build UTM links with clear source, medium, campaign, term, and content fields.
16

tools available

16

guides available

Free

No signup needed

What this category helps with

  • Technical browser utilities for subnetting, passwords, encoding-style tasks, and developer checks.
  • Local-first tools that avoid sending sensitive technical inputs to a server.
  • Research-backed notes for standards-sensitive workflows such as CIDR and password generation.

Start with these tools

Subnet Calculator Calculate IPv4 CIDR network, broadcast, mask, wildcard, and usable host range. Password Generator Generate strong random passwords with length, character sets, and ambiguity controls. Base64 Encode / Decode Encode UTF-8 text to Base64 or decode Base64 back to text. URL Encode / Decode Percent-encode URL component text or decode percent-encoded text. Bandwidth Calculator Estimate file transfer time from data size and network bandwidth. JSON Formatter Format and validate JSON with two-space indentation and optional sorted object keys.

All developer utilities

Open a tool, try the examples, then use the matching guide when you need more explanation.

Subnet Calculator Calculate IPv4 CIDR network, broadcast, mask, wildcard, and usable host range. Open Password Generator Generate strong random passwords with length, character sets, and ambiguity controls. Open Base64 Encode / Decode Encode UTF-8 text to Base64 or decode Base64 back to text. Open URL Encode / Decode Percent-encode URL component text or decode percent-encoded text. Open Bandwidth Calculator Estimate file transfer time from data size and network bandwidth. Open JSON Formatter Format and validate JSON with two-space indentation and optional sorted object keys. Open UUID Generator Generate UUID v4 identifiers with quantity, uppercase, and hyphen options. Open Hash Generator Generate SHA-256, SHA-384, or SHA-512 text digests in hexadecimal format. Open UTM Builder Build campaign URLs with source, medium, campaign, content, and term parameters. Open Query String Parser Parse URL query strings into JSON or build encoded query strings from key-value lines. Open HTML Entity Encoder / Decoder Encode HTML-sensitive characters or decode common named and numeric HTML entities. Open CSS Clamp Calculator Generate CSS clamp formulas for fluid font sizes, spacing, and responsive layout values. Open API Pricing Calculator Estimate API usage cost from request count, units per request, unit price, fees, and overhead. Open Download Time Calculator Estimate how long a file, game, backup, or update will take to download. Open Internet Speed Needs Calculator Estimate a household or workspace internet speed need from simultaneous activities. Open Streaming Bitrate Calculator Estimate stream or recording data use from bitrate, time, and stream count. Open

Guides for this category

Each guide uses its matching tool, with example numbers and plain limits.