Yavida
Free calculators differ in three quiet ways that matter a lot: which emission factors they use, how many years those factors have been updated, and how much of Scope 3 they attempt to cover at all. None of that shows up on a homepage. It shows up when you compare two tools against the same month of data and get noticeably different numbers.
Four categories, one shared caveat
What it is
Downloadable spreadsheets built around the GHG Protocol Corporate Standard, letting you enter activity data manually into predefined categories.
Where it's strong
Transparent formulas, flexible enough for an unusual business, and grounded in the most widely referenced accounting standard.
Where it's limited
No Czech-specific defaults, and you're responsible for choosing correct emission factors yourself, which takes some learning.
What it is
Web forms aimed at smaller businesses, often produced by EU-supported climate initiatives, asking for a handful of simple inputs.
Where it's strong
Fast to use, standardised categories, and a gentle learning curve for a first-time user with no reporting background.
Where it's limited
Scope 3 is usually shallow, sometimes limited to one or two default categories rather than your actual supply chain.
What it is
Tools published by national business associations or chambers of commerce, sometimes using country-specific grid figures.
Where it's strong
Czech-language interfaces and a national electricity grid factor rather than an EU-wide average, which can shift results meaningfully.
Where it's limited
Update frequency varies by publisher, and documentation of methodology is sometimes thinner than you'd like before relying on it.
What it is
Calculators built by trade associations for a specific sector, such as food production, with categories tailored to that industry.
Where it's strong
Categories that actually match your operations, like oven types or refrigeration classes, rather than generic business inputs.
Where it's limited
Coverage and maintenance depend entirely on the association's resources, and not every sector has one that's kept current.
Before you trust a result
A 2018 electricity factor and a 2024 one can differ substantially as national grids change. Check the publication date before trusting a total.
Some tools quietly exclude leased assets or franchise locations. Read the small print on what counts as "your" operations.
The GHG Protocol lists fifteen possible Scope 3 categories. Most free tools cover two or three of them, rarely all fifteen.
Tools maintained by a single volunteer team can lag behind regulatory changes. Look for a visible changelog or version note.