Adaface vs Testlify
By Sergio Gualda · 5 min read · Updated
Adaface runs scenario-based tests of around forty minutes from a library its site puts at 500+, with unusual depth in engineering — coding across 35+ programming languages and 20+ frameworks, plus cognitive ability and business tools. Testlify's site puts its library at 3,500+ validated tests covering 5,000+ roles in 9+ languages with 25+ question formats. They are the same category of product making opposite bets. One question generally resolves it: if you listed every role you will hire for in the next year, what fraction is engineering? Above roughly half, Adaface's depth is the product you are buying. Below it, Testlify covers more of your actual problem.
Written by uxerhub, which sells a competing product for six product roles. Everything below about Adaface and Testlify comes from their own public sites. Where we fit is at the end, in its own section, and you can skip it.
Adaface and Testlify, side by side
| Adaface | Testlify | |
|---|---|---|
| Library size | 500+ tests, concentrated. | 3,500+ validated tests across 5,000+ roles. |
| Engineering depth | The centre of the product — 35+ programming languages, 20+ frameworks, SQL, data analysis. | Covered within a much wider catalogue, without the same concentration. |
| Non-technical coverage | Cognitive ability and business tools; not built to staff a whole company. | Extensive, and the reason most buyers choose it. |
| Languages | English-led. | 9+ languages. |
| Question style | Scenario-based questions about the actual job rather than abstract puzzles. | 25+ formats, including situational judgment tests. |
| Typical length | Around forty minutes. | Varies with the tests you assemble. |
Which one you should pick
Choose Adaface if
- Most of your hiring is engineering and you need the real stack tested, not an adjacent one.
- You want questions that resemble the job rather than puzzles.
- Forty minutes of candidate time is acceptable for your roles.
- You would rather be strong on your main hiring problem than adequate everywhere.
Choose Testlify if
- You hire across many functions and keep hitting gaps in smaller libraries.
- You hire outside English-speaking markets.
- You fill unusual roles where a general library runs out.
- You want to start today without a card or a call.
One question decides this, and it is not about the products
List the roles you filled in the last twelve months and the ones you expect to open in the next twelve. Count what fraction is engineering.
If it is most of them, Adaface's depth is not a nice-to-have — testing the actual language and framework rather than an approximation removes a whole class of candidates wrongly filtered out, and a general library rarely reaches that far.
If engineering is a minority, the depth is a strength you will use a few times a year while buying a second product for everything else. At that point coverage wins and the size gap between the libraries becomes the deciding fact rather than a marketing number.
Very few teams need to think harder about this than that exercise requires, and doing it takes ten minutes.
What neither library reaches
Both of these are strongest where the answer can be checked. That is a genuine strength and it is the reason skills testing works at all: code either compiles or it does not, a SQL query either returns the right rows or it does not.
It is also the boundary. For roles where the expensive decisions have no correct answer — what to build, what to cut, when to push back on a brief that arrived already decided — a verifiable test cannot reach the thing that separates good from adequate, because the thing is a judgement rather than an answer.
That is not a criticism of either product. It is a reason to be clear about which half of a person a skills test has measured before treating a pass as the end of the assessment.
Disclosure · our own product
Where uxerhub fits, if neither is quite it
uxerhub is built for exactly the half described above, and only for product roles: product designer, product manager, UX researcher, design engineer, front-end engineer and UX writer. Twelve written situations, no correct option among them, scored against the capabilities you name as essential for the specific job.
For engineering hires it is a complement and not a substitute. If you run only uxerhub on a front-end engineer you will know how they decide and nothing about whether they can ship, which is why we recommend keeping a coding test regardless.
The honest limits: six roles, English only, and not calibrated yet — the scoring is deterministic arithmetic but we have not published predictive validity. Adaface's technical library has an evidence base for its question that we do not yet have for ours.
Frequently asked
- Which is better for hiring engineers?
- Adaface, on its own published numbers: coding across 35+ languages and 20+ frameworks is a depth Testlify's broader catalogue does not concentrate on. If engineering is the bulk of your hiring, that is the deciding factor.
- Which has better coverage for non-technical roles?
- Testlify, clearly — 3,500+ tests across 5,000+ roles in 9+ languages against a library built primarily around technical and cognitive ground.
- Are Adaface's tests really scenario-based?
- That is its stated design principle: questions about the actual job rather than trick puzzles. It is a meaningful distinction from libraries built on abstract aptitude items, and it is worth checking against the specific tests you would actually send.
- Can you use both?
- Some teams do — Adaface for engineering and Testlify for everything else — but it means two subscriptions and two candidate experiences. It is usually only worth it when engineering volume is high enough to justify the depth on its own.