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N NizNext Local

11 tools · client-side · 0 bytes leave your device

Everything runs
inside your browser.

Your files, listings and numbers are processed by your own machine using the File, Canvas and WebCrypto APIs. There is no upload step, no queue, no account, and nothing to delete afterwards, because we never received it.

Showing 11 of 11 tools No sign-up No watermarks Works offline after first load

Where it runs

Your CPU. Files are read with the browser File API and never attached to a network request.

What we store

Your theme choice, in localStorage. That is the complete list.

How to verify

Open DevTools, watch the Network tab, then process a file. Nothing outbound.

Sell, price & convert

E-Commerce & Everyday Utilities

11 tools
Marketplace Fee Calculator Net payout after eBay, Amazon, Etsy and Shopify fees. Sales Tax & VAT Calculator Add or strip tax across GST, HST, VAT and US state rates. Marketing ROI Calculator Work out ROAS, break-even and profit per ad dollar. Dimensional Shipping Estimator Compare DIM weight against actual weight before you ship. Market-Specific Title Generator Build titles that fit each marketplace's character limit. Marketplace Description Generator Turn specs and features into a formatted listing body. Product Image Studio Crop, pad and square product shots to marketplace specs. Meta & Google Ad Copy Generator Draft headlines and primary text inside platform limits. Barcode Generator Create UPC, EAN and Code 128 barcodes as SVG or PNG. Listing Character Counter Count characters, words and bytes against per-field caps. Unit Converter Length, weight, volume, area, speed and temperature.

Common questions

How NizNext Tools works

Are files uploaded to a server?

No. Every tool reads your file with the browser File API and processes it with Canvas, WebCrypto or plain JavaScript on your own device. No file is ever attached to a network request, so there is nothing on our side to store or delete.

Do I need an account?

No. There is no sign-up, no email capture and no usage limit. Open a tool and use it.

Do the tools work offline?

Yes, once a tool page has loaded. The processing logic runs locally, so after the page and its assets are cached the tool keeps working without a connection.

How can I verify nothing leaves my browser?

Open your browser developer tools, switch to the Network tab, then run a file through any tool. You will see no outbound request carrying your data.