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What Can We Help With?
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Bug Reports — Found an incorrect result or a broken feature?
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Feature Requests — Want a new calculator type or layout option?
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Math Questions — Confused about modular arithmetic or a result?
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Partnerships — Interested in linking to or collaborating with us?
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Legal / Privacy — Questions about our policies or data?
Quick Answers
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Why is my result different from some programming languages?Our calculator always uses the mathematical modulo definition — the remainder is always ≥ 0. Some languages like C/Java return negative remainders for negative dividends. Python and our tool always return non-negative results.
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Is the calculator free for commercial use?Yes — ModCalculator.org is 100% free for personal and commercial use. No account, no attribution required.
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Do you store my calculation inputs?No. All calculations run locally in your browser. Nothing is ever sent to our servers. Your data stays completely private.
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Can I embed this calculator on my website?Yes! Contact us using the form and we'll help you set up an embed link. We're happy to support educational sites, blogs, and tools.
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