How the BookBird Author Score Works

The formula in short

• Author jobs, 50 points. Each kind of software has a list of jobs a self-published author needs it to do. A product earns points for each job its own website confirms.
• Cost, 25 points. What one year of use costs a single author on the cheapest plan. Free earns all 25.
• Adoption, 25 points. How many people in the US search Google for the product by name each month, and whether that is rising or falling.

The points are added up and turned into a score out of 10. A product is only compared with the others in the same category, so an app that is both a writing app and a formatter has two scores.

A worked example: Vellum as a formatter

Vellum’s own site confirms 8 of 8 formatting jobs, which earns 50 of 50 points. Its cheapest licence is $199.99, paid once; spread over three years that is $66.66 a year, the highest among formatters with a confirmed US price, so it keeps the minimum 5 of 25. About 320 people a month search for “vellum book formatting”, up over the year, which earns 15.7 of 25. In total that is a score of 7.1 out of 10. The same breakdown, with the reason for every point, sits under the score on Vellum’s page and on every other product’s page.

Author jobs: what we check

The jobs are what an author needs from that kind of software to write, publish or sell a book, such as exporting an EPUB and a print-ready PDF in KDP trim sizes for a formatter, or stating that your text is not used to train AI for an editing tool. The full list for each category is in the formula below.

A job counts only when the vendor’s own pages say the product does it: its features, pricing, help and policy pages. We do not count marketing claims that do not describe the capability, and we do not count what reviewers or forums say. A job the vendor does not mention earns nothing and is shown as “not stated”; one the vendor says it does not do is shown as “no”. That means a product can be better than its score if its website undersells it, and the fix is for the vendor to describe the feature.

Cost

We take the cheapest way for one author to use the product for a year, in US dollars as printed on the vendor’s site. A monthly plan counts twelve months. For software, a one-time licence is spread over three years, so it can be compared with a subscription. For services an author pays per book (an ARC campaign, an audiobook, a publishing package), a one-time price counts as one book’s cost. Optional extras such as an ISBN or an upgrade do not count as the price. A free plan, or a platform that charges nothing up front and takes a share of sales, earns all 25 points; the dearest product in the category keeps 5, and the rest fall in between in a straight line. If no US dollar price could be confirmed, Cost is left out rather than guessed.

Adoption

How widely a product is used is hard to measure directly, so we use how often people search for it by name: US Google searches a month, from Google Ads data via DataForSEO. Where a name is an ordinary word, we search the name with a qualifier (“vellum book formatting”, not “vellum”). 20 points go to the volume, on a log scale against the most searched product in the category, so a product with a tenth of the leader’s searches still earns a good share. The other 5 go to the trend: the last three months against the first three of the year.

What we do not score, and why

• Writing quality and ease of use. We did not test the apps by writing a book in them, so we do not rate how they feel to use.
• Review sites. For most of these products, the Trustpilot or G2 profile rates the whole company, or holds a handful of reviews, and some sites block automated reading. A score built on them would measure the vendors’ marketing more than the software.
• Age. Few vendors state when a product launched, and a website’s age often predates the product, so we leave it out.
• Affiliate commissions. If a vendor ever pays us a commission on sales through our link, that is never part of the score, and the link is marked as sponsored.

Where the data comes from, and when

Every fact was read from the vendor’s own website on October 7, 2026, and the address it came from is recorded. Search volumes are from the same week. We re-check the data and recompute every score together, so all scores in a category always come from the same date. If a vendor’s page or price has changed, or you spot a mistake, write to [email protected] with the link and we will check it.

Browse the scores: all software for authors.