Embeddable validator widgets
Free, no sign-up, no API key. Validation runs locally in the visitor's browser inside a sandboxed iframe — numbers are never uploaded. Two lines of HTML.
CPF / CNPJ Validator (Brazil)
Option A — script tag (default height 210px, set data-height to adjust)
<script src="https://momo24.tools/widget/embed.js" data-widget="cpf" async></script>Option B — plain iframe
<iframe src="https://momo24.tools/widget/cpf/" title="CPF / CNPJ Validator (Brazil) — momo24.tools"
width="420" height="210" loading="lazy" sandbox="allow-scripts allow-same-origin allow-popups allow-popups-to-escape-sandbox"
style="border:1px solid rgba(128,128,128,.25);border-radius:12px"></iframe>Full tool with batch mode: momo24.tools/tools/cpf-cnpj-validator/
GSTIN Validator (India)
Option A — script tag (default height 210px, set data-height to adjust)
<script src="https://momo24.tools/widget/embed.js" data-widget="gstin" async></script>Option B — plain iframe
<iframe src="https://momo24.tools/widget/gstin/" title="GSTIN Validator (India) — momo24.tools"
width="420" height="210" loading="lazy" sandbox="allow-scripts allow-same-origin allow-popups allow-popups-to-escape-sandbox"
style="border:1px solid rgba(128,128,128,.25);border-radius:12px"></iframe>Full tool with batch mode: momo24.tools/tools/gstin-validator/
Terms
Widgets are free for any site. They perform a format and check-digit pre-check only — they do not query government databases and do not prove a number exists, is active, or belongs to anyone. Please keep the “Powered by momo24.tools” link visible.