§ The result
1 point separates Mercer | Mettl and Willo.
Mercer | Mettl (Assessment) edges Willo (Video interview) by 1 point under rubric v1.0, 42 to 41. Mercer | Mettl leads 4 of the 7 criteria, including Bias Audit Transparency, while Willo leads 2, including Human Oversight Design, and 1 is level. Mercer | Mettl takes the heaviest weighted swing, Bias Audit Transparency at 18% (Mercer | Mettl 42, Willo 30), which is 69% of the weighted advantage Mercer | Mettl holds; the widest raw gap is a different criterion, Human Oversight Design, Mercer | Mettl 45 to Willo 62.
Vendor profile
Mercer | Mettl
Mercer | Mettl is an online talent assessment and remote-proctoring platform offering psychometric, aptitude, coding, and skills tests plus AI-assisted exam proctoring and scoring for hiring, certification, and L&D.
Vendor profile
Willo
Willo is a browser-based asynchronous (one-way) video interview platform that lets employers collect recorded video, audio, multiple-choice and written candidate responses, then uses AI to transcribe, summarize, rank candidates against employer-defined "Blueprint" criteria, and flag scripted or AI-generated answers.
§ The record
Mercer | Mettl is filed under Assessment AI, Willo under Video interview AI. They also share 1 secondary category: Screening.
Both are in scope of NYC LL 144, Illinois HB 3773, EU AI Act, Colorado AI Act and Mobley v. Workday.
| Record | Mercer | Mettl | Willo |
|---|---|---|
| Price tier | Mid | Low |
| Headquarters | IN | GB |
| Founded | 2010 | 2018 |
§ What decides it
The criteria that move the gap, heaviest swing first.
18% weight · 40% of the movement so far
Bias Audit Transparency
Mercer | Mettl 42 · Willo 30
2.2 weighted points to Mercer | Mettl
12% weight · 79% of the movement so far
Human Oversight Design
Mercer | Mettl 45 · Willo 62
2.0 weighted points to Willo
15% weight · 87% of the movement so far
FRIA Support
Mercer | Mettl 28 · Willo 25
0.4 weighted points to Mercer | Mettl
15% weight · 93% of the movement so far
Data Governance Disclosure
Mercer | Mettl 55 · Willo 53
0.3 weighted points to Mercer | Mettl
12% weight · 97% of the movement so far
Post-Market Monitoring
Mercer | Mettl 38 · Willo 36
0.2 weighted points to Mercer | Mettl
8% weight · 100% of the movement so far
Customer Documentation
Mercer | Mettl 52 · Willo 54
0.2 weighted points to Willo
Weighted delta is the raw difference times the criterion weight, so the 6 figures above sum to +1.0 — the difference between the two totals before either is rounded. Shares are of 5.4 points of movement counted without direction. The table below rounds each side to a whole number first, so its Δ raw total reads +1 beside that +1.0.
§ Category-by-category
Raw score per criterion, with weighted delta.
Δ is Mercer | Mettl minus Willo.
| Category | Weight | Mercer | Mettl | Willo | Δ raw | Δ weighted |
|---|---|---|---|---|---|
| Article 11 Technical Documentation | 20% | 38 | 38 | - | - |
| Bias Audit Transparency | 18% | 42 | 30 | +12 | +2.2 |
| FRIA Support | 15% | 28 | 25 | +3 | +0.4 |
| Data Governance Disclosure | 15% | 55 | 53 | +2 | +0.3 |
| Human Oversight Design | 12% | 45 | 62 | -17 | -2.0 |
| Post-Market Monitoring | 12% | 38 | 36 | +2 | +0.2 |
| Customer Documentation | 8% | 52 | 54 | -2 | -0.2 |
| Total | 100% | 42 (F) | 41 (F) | +1 | +1.0 |
§ Evidence
Cited sources and documented absences, criterion by criterion.
An absence is a finding, not a blank: the reviewer looked for a named artefact and recorded that it is not located. Where a source sits is a fact about hosting only.
| Criterion | Weight | Mercer | Mettl | Willo | ||||
|---|---|---|---|---|---|---|---|
| Cited | Absences | Audit / hosting | Cited | Absences | Audit / hosting | ||
| Article 11 Technical Documentation | 20% | 2 | 1 | Sources on the vendor's own domain | 2 | 1 | Sources on the vendor's own domain |
| Bias Audit Transparency | 18% | 0 | 1 | — | 1 | 1 | — |
| FRIA Support | 15% | 1 | 1 | — | 0 | 1 | — |
| Data Governance Disclosure | 15% | 2 | 0 | Sources on the vendor's own domain | 2 | 0 | Sources on the vendor's own domain |
| Human Oversight Design | 12% | 2 | 0 | Sources on the vendor's own domain | 2 | 0 | Sources on the vendor's own domain |
| Post-Market Monitoring | 12% | 1 | 1 | Sources on the vendor's own domain | 1 | 1 | Sources on the vendor's own domain |
| Customer Documentation | 8% | 1 | 1 | Sources on the vendor's own domain | 1 | 1 | Sources on the vendor's own domain |
| All criteria | 100% | 9 | 5 | Sources on the vendor's own domain | 9 | 5 | Sources on the vendor's own domain |
Mercer | Mettl has 14 evidence rows across 7 of 7 criteria — 9 with a source URL, 5 documented absences; Willo has 14 evidence rows across 7 of 7 criteria — 9 with a source URL, 5 documented absences.
Provenance
The scores above are documented by 28 evidence rows on file for these two vendors: 14 for Mercer | Mettl, across 2 distinct source domains, and 14 for Willo, across 1 distinct source domain.
- Rubric
- v1.0
- Mercer | Mettl last reviewed
- June 7, 2026 · HireAIScore editorial team
- Willo last reviewed
- June 7, 2026 · HireAIScore editorial team
HireAIScore scores are editorial research, not legal advice, and no vendor pays for placement, scoring or removal — see the methodology, conflicts policy and terms.
§ Where next