Markets ›api testing software 38 brands
Postman is named most often — in 36 of 36 answers. 6 questions a buyer would type, asked of 2 assistants 3 times each.
13 brands in this market were named in none of the 36 answers: AWS API Gateway, Advanced REST Client, Apigee, AsyncAPI, Datadog, GitHub, GitHub Actions, GitLab and 5 more.
Being a big website barely predicts being named here. The assistants are drawing on something other than raw web prominence.
↑how often assistants name it →how much traffic its website gets
Across is web prominence — the brand's domain in the Tranco ranking of the world's most-visited sites, on a logarithmic scale, so each step is roughly ten times more prominent. Up is how many of the 36 answers named it.
Every brand with a ranked domain is plotted, including the 1 whose domain is an imperfect stand-in — shared with sibling products, a subdomain, or registered abroad, drawn hollow — because a domain carrying a whole company still plausibly helps that company's products get named. Brands checked against the list and not found sit in the "not ranked" band at the left: their websites are known to be outside the top million, which is a measurement rather than a gap. Brands whose rank belongs to a parent domain, and those never checked, are not plotted at all — an unknown rank cannot be placed. Not plotted, having no ranked domain: Thunder Client, ReadyAPI, REST Assured, JMeter, Karate, Talend API Tester and 1 more.
Rank correlation +0.05 across 13 brands — a description of this picture, not a claim about the market as a whole.
The questions
These belong to the market, not to any brand in it. Each was asked 6 times across two assistants. Questions naming a brand are excluded, since they hand that brand a free mention.
Want to get weekly ranking updates? Leave your email above.
Method
market api testing software
brands measured 38
run as subjects 1
questions 6
answers per brand 36
brand list version a31e52e6bc2f
Questions went to the OpenAI and Anthropic APIs with web search off, each in a fresh context with no history. That measures what the models already know about these brands rather than what they would find on the web today, so it is a floor on visibility rather than a replica of any one person's chat.
Repeated measurements of the same brand move within about 12 points, so a difference smaller than that is not meaningful. Brands closer together than that are shown tied rather than ordered.
Sub-brands are counted with their parent: Postman (Newman); Swagger (Swagger Editor, Swagger UI).
How the table is ordered. By how many of the 36 answers named each brand. Brands on the same count share a rank and are shown in the order the assistants tended to list them. A brand counts once per answer, however many times it is named in it.
How close is close. Two brands share a rank only when their counts are identical. Beyond that, a gap smaller than about four answers is inside what this measurement moves between runs — so read near-neighbours as close rather than settled, which is why every row keeps its interval.