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Development tools

Web developer tools for making your dev tasks that litte bit easier.

8-Bit Chiptunes Creator

Create authentic 8-bit chiptunes music. Pattern sequencer, NES/C64/Game Boy sound chips, tracker interface, arpeggiator, effects, and WAV export. 30-300 second compositions.

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Assembly Instruction Visualiser (8086)

Type simple 8086 assembly, see the opcodes, step through execution, and watch registers and flags update in real time. Share links and export bytes.

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Binary Code Converter

Convert between binary, decimal, hexadecimal and text. Clean UK-friendly tool with live updates, spacing options, and shareable links.

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Color Contrast Checker - WCAG Compliance

Check color contrast ratios for WCAG AA and AAA compliance. Test accessibility, preview text samples, simulate color blindness, and generate accessibility reports.

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CSS Grid System Calculator

Generate responsive CSS grid systems with custom columns, gutters, and breakpoints. Visual preview, CSS code export, and flexible layout calculations for web design.

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Custom Stylesheet Generator - Build Your CSS

Generate custom CSS stylesheets by selecting only the components you need. Perfect for beginners - choose buttons, forms, typography, and more from popular frameworks.

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Dial-Up + ZX Loader Generator Pro

Generate epic 90s dial-up modem sounds with 80s ZX-style loading visuals. Extended durations up to 90 seconds. Play, customise, export WAV, and share. All in your browser.

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DOS 8.3 Filename Generator & Validator

Convert long filenames to DOS 8.3. Validate, normalise, and resolve collisions with a tilde suffix. Batch mode, copy link and CSV export.

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IP Subnet Calculator

Calculate IPv4 subnets from a CIDR or IP and subnet mask. Get network, broadcast, usable range, wildcard and host counts. Shareable links and CSV export.

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JWT Debugger - Decode & Inspect JSON Web Tokens

Debug and decode JWT tokens online. Inspect headers, payloads, claims, and validate token structure. Educational JWT tool for developers.

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Regex Tester - Test & Debug Regular Expressions

Test and debug regular expressions with real-time matching, visual explanations, and code generation. Supports JavaScript, PHP, Python regex flavors with pattern library.

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SFV / CRC32 Checker

Calculate CRC32 checksums and create or verify SFV files. Multi-file, drag-and-drop, copyable results and export, all client-side.

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SQL Query Builder - Visual Database Query Generator

Build SQL queries visually with our interactive query builder. Supports SELECT, INSERT, UPDATE, DELETE with JOIN operations, subqueries, and multiple SQL dialects.

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ZX Spectrum Tape Loader Pro

Ultimate ZX Spectrum tape loader simulator. Multiple games, authentic loading screens, pilot tones, data blocks, loading errors, and turbo loaders. 30-300 second sequences with WAV export.

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Web Development Tools

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