Free tools for the trades
Calculators and templates you can use right away — no signup.
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Business & pricing
Hourly rate calculator
What does your hour have to cost for the business to carry itself?
OpenQuote templates per trade
Sample positions and pro tips for your quote — now in the template hub with Word and PDF downloads.
OpenMaterial markup calculator
From purchase price to sales price: add your markup and see gross profit and margin instantly.
OpenMargin & markup calculator
Convert between margin and markup from purchase and sales price.
OpenQuote estimator
Work out the quote price from labour hours, materials, overhead and risk & profit.
OpenBusiness valuation calculator
Estimate a rough business value for succession or sale using the multiplier method.
OpenTrade business check
7 questions on process and digitalisation — find out where your business stands.
OpenLaw & invoicing
E-invoice quick check
Paste XML — detect the format and check core fields. Right in your browser.
OpenFollow-up templates
E-mail texts for quote follow-ups and payment reminders — ready to copy.
OpenSmall-business rule calculator (§19)
Check whether you stay within the turnover limits of the German small-business rule (§19 UStG).
OpenVAT calculator (gross/net)
Add or remove VAT — for 19% or 7%.
OpenEarly-payment discount calculator
Calculate the discount, the amount due and the effective annual rate of the discount.
OpenLate-payment interest calculator
Calculate late-payment interest and the flat compensation under §288 BGB.
OpenTechnical & estimating
Heating load calculator
Rough heating load of a room or building from area and insulation standard.
OpenAir flow rate calculator
Required air flow from room size and target air-change rate.
OpenAir-change rate calculator
Determine air-change rate n from a known air flow and room size.
OpenDuct size calculator
Duct diameter from air flow and air velocity.
OpenFlow rate calculator
Flow rate from pipe diameter and flow velocity.
OpenPipe volume calculator
Pipe content in litres from inner diameter and length.
OpenHeating power calculator (kW/BTU)
Convert power between kW, BTU/h and kcal/h.
OpenRoof area calculator
Sloped roof area from footprint and roof pitch.
OpenHeating cost savings calculator
Estimate annual savings from a more efficient heat generator.
OpenMaterial quantity calculator
Required material or paint quantity from area, coverage and waste.
OpenMore tools are coming. Wishes? Tell us via the contact page.
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