Free Tools
Thirty free calculators for the practical questions of city life, in three toolsets. They run entirely in your browser: no sign-up, no account, and what you type into them is not sent anywhere.
Most people cannot tell whether an exit is wide enough, a rooftop can harvest useful rainwater, or a stamp-duty quote is right.These tools turn those questions into a two-minute calculation with a clear answer and, where it applies, the next step to take.
Step by step.
Safety and structure
Fire exit clearance, seismic risk, structural load, pothole risk, crowd density, acoustic comfort, air quality, flood risk, rooftop solar and infrastructure checks.
Environment and resources
Rainwater harvesting, per-person water use, greywater reuse, urban heat island, garden and compost planning, solar, biogas, tree offset, EV and carbon footprint.
Civic and everyday
Walkability audit, water tanker cost, streetlight, total cost of ownership, society maintenance, electricity bill, property tax, stamp duty, movers cost and an RTI request generator.
Use the result
Several tools end with a suggested action, such as which authority to write to or what to ask for.
The details.
Safety tools
Ten calculators for buildings, crowds and hazards.
Open →ToolsetEnvironment tools
Ten calculators for water, energy and carbon.
Open →ToolsetCivic tools
Ten calculators for money, property and citizen rights.
Open →- Cost
- Free, no sign-up
- Runs in
- Your browser only
- Tools
- 30 across three toolsets
- Data sent
- None: inputs stay on your device
Try the tools
Pick a toolset and get a result in a couple of minutes.