Darikwa logodarikwa
The Lab — 10 live tools, free to use

Put a numberon the problem.

Interactive calculators built from real UK operational experience. Free to use, no sign-up required. Move the inputs, share the link.

I

Tax & Compliance

Tax & Compliance

UK VAT Calculator

Add or remove VAT at 20%, 5% or 0% with one click.

Open the tool →

Tax & Compliance

UK Mileage Claim Calculator

HMRC approved mileage rates for cars, motorcycles and bicycles.

Open the tool →

II

E-Commerce

E-Commerce

Shopify Fee & Profit Calculator

Real monthly cost and net profit per order on every Shopify plan.

Open the tool →

E-Commerce

Retail Margin & Markup Calculator

Convert between cost, price, margin and markup without confusion.

Open the tool →

III

Financial Planning

Financial Planning

ROI Estimator

Size the annual margin uplift from fixing operational leaks.

Open the tool →

Financial Planning

Break-Even Calculator

Units and revenue you need to cover fixed and variable costs.

Open the tool →

Financial Planning

CAC & LTV Calculator

Acquisition cost, lifetime value and payback period at a glance.

Open the tool →

IV

Operations

Operations

Recruitment Cost Calculator

True cost of hiring including agency fees, onboarding and ramp.

Open the tool →

V

Import & Trade

Import & Trade

Landed Cost Calculator

Total landed cost per unit including duty, freight and clearance.

Open the tool →

Import & Trade

UK Import Duty & VAT Calculator

Estimate customs value, duty and import VAT for UK imports.

Open the tool →

§

In the workshop.

Coming soon

12-Week Cash Flow Forecast

Weekly cash position with threshold alerts and shareable links.

Coming soon

HS Code Lookup & MID Generator

Find commodity codes and generate US customs MID codes.

§

Just for fun.

Not everything I build has a business case. It isn't all serious business here — we have fun as well.

Arcade

Pac-Swipe

A swipe-controlled Pac-Man style arcade break, built for this site. Eat the dots, dodge the ghosts. More games on the way.

Take a break →

§

Looking fordownloadable templates?

Excel and PDF templates — cash flow, buy plans, board packs, recruitment planners and more.

Browse templates