ABOUT TWELVE TOOLS
A portfolio of focused tools.
We are a small Munich-based company that builds single-purpose web utilities. Each one runs on its own subdomain, owns its own deployment, and does one job well — without becoming a platform, a workspace, or an account-system.
The company
Twelve Tools is operated by Twelve Digital GmbH, a software company registered in Munich (HRB 311580, Amtsgericht München). We have been publishing small web utilities since 2024. The company also builds inspection software for regulated industries — the tools portal exists because we kept needing tiny, focused calculators and converters for our own work and decided to publish the ones that proved generally useful.
Each public tool is funded by display advertising and is free for end users. We do not require accounts, do not collect uploaded files, and process most data directly in the browser when the file format makes that possible.
Why single-purpose tools?
Every tool in this portfolio does one job. We don't try to be a platform, a workspace, or an account-system. You arrive at a URL, the calculation or transformation happens, you leave with the result. No onboarding, no dashboard, no upsell.
That focus has consequences we like. The pages load fast because they ship almost nothing. They run in your browser so the data stays on your machine where the file processing makes that possible. They survive without our servers being up — open the page once, your laptop has the engine cached. And they age gracefully: a single-purpose tool gets sharper with each iteration instead of bloated with unrelated features.
Each tool also lives at its own subdomain (rechenwerk.twelve-tools.com,
solar.twelve-tools.com, etc.) so we can rev them independently. Updates to
the solar simulator can ship without touching the German tax calculators, and a tool can
be retired without affecting the others.
How we handle data
Where the underlying file format allows it, processing happens entirely client-side. PDF merge/split runs on your machine via pdf-lib — your files do not reach our servers. Image background removal and image comparison work the same way. The German tax calculators do their math in pure JavaScript, never sending the inputs over the wire.
Solar yield is the exception: it queries the European Commission's PVGIS irradiance dataset on your behalf, which means your chosen coordinates are forwarded to that public-sector API. That's the only tool here that requires a backend round-trip during normal use.
On the individual tool subdomains, site analytics and ad personalization run only after explicit cookie consent, in line with the GDPR — each of those pages carries a consent banner with a settings link in the footer. The portal page you are reading uses no analytics or ad cookies of its own. Full details on what is collected where are on the privacy page.
Get in touch
For questions about a specific tool, feedback, bug reports, or business inquiries, the fastest channel is email at info@twelve-digital.de. For postal correspondence, see the imprint.