How Dioveo estimates the CO2 impact of emails

Dioveo shows a CO2 estimate because email is not free. Every email uses electricity to travel across networks and to live in storage. The numbers you see in Dioveo are not exact measurements. They are practical estimates meant to help you understand scale and make cleanup decisions with more context.

This post explains the approach in plain language.

Why there are two calculations

Dioveo uses two different methods depending on what you are doing:

• A method for a single email

• A method for cleaning up many emails at once

We do this because bulk cleanup can be more efficient than repeating the same work email by email.

1. Estimating CO2 for a single email

For one email, we use two simple ideas.

First, every email has a small base cost, even if it is tiny.

Second, bigger emails usually have more impact than smaller ones, especially when they include attachments.

So our estimate is:

• Base cost: 4 grams of CO2 per email

• Plus an extra amount that depends on the email size

For small emails the impact grows in a simple way. For large emails we slow down the growth so the estimate does not explode for very big attachments.

We also cap the result to avoid extreme outliers.

2. Estimating CO2 for bulk cleanup

Cleanup is different. If you delete or process many emails together, the system can do it more efficiently than if you repeat the same work one email at a time.

So for cleanup operations we use:

• A lower base cost per email

• A size based estimate based on the total amount of data

• A bonus for bulk efficiency

In practice, this means bulk cleanup shows a smaller impact per email than doing the same cleanup one by one.

Making the numbers easier to understand

CO2 grams are hard to picture, so Dioveo adds comparisons.

For example:

• Tree equivalence, to give a sense of yearly absorption

• Everyday comparisons, so the impact feels more concrete

These comparisons are not perfect science. They exist to make the numbers understandable.

What this calculation is good for

This estimate is useful for:

• Comparing which cleanup actions have more impact

• Understanding how attachments change the footprint

• Getting a sense of scale in a large inbox

It is designed to be consistent and easy to interpret inside the product.

What this calculation is not

A few important limits:

• It is an estimate, not a measurement

• Real impact depends on many factors outside the inbox

• The goal is guidance, not precision

One more important thing

Nothing is deleted automatically. Cleanup suggestions are always reviewed first.

Feedback welcome

If you have suggestions or think we should improve the model, we would love to hear from you.