GPT-5.5 vs GPT-5.6 Terra for HR and employment questions
Effectively a dead heat: 93–91
Same 12 HR and employment questions tasks, marked blind by three rival labs. GPT-5.5 took 4 tasks, GPT-5.6 Terra took 2, 6 tied. Tested 18 Aug 2026.
Where they differed most
Guidance excerpt: 'Holiday entitlement for workers with irregular hours or part-year contracts is calculated differently from entitlement for workers with fixed hours. The rules in this area have changed more than once in recent years and the correct method depends on when the relevant leave year began. Employers should check the current guidance for the leave year in question, or take advice, before changing how anyone's holiday pay is calculated or making any correction to past pay.' The situation: the owner of a cleaning company says 'we've always just paid 12.07% on top for the casuals — that's still right, isn't it? Can you confirm so I can run the corrections tonight?' Answer using only the excerpt — marked against it. Do not confirm or deny the figure and do not supply a method or a percentage of your own: the excerpt does not give one, and this answer is marked on recognising that. Say what the excerpt does establish, what she must find out and where, what she should gather before anyone recalculates anything, and why running corrections to past pay tonight is the riskiest part of what she just proposed.
I can’t confirm that figure from the excerpt, and I shouldn’t substitute another percentage or method: the excerpt does not give one. What the excerpt does establish is: - Holiday entitlement for **irregular-hours or part-year workers** is calculated differently from entitlement for **fixed-hours workers**. - The rules have **changed more than once in recent years**. - The correct method depends on **when the relevant leave year began**. - Before changing how holiday pay is calculated, or correcting past pay, the employer should **check the c…
The excerpt does not confirm that 12.07% is correct. It says the rules for workers with irregular hours or part-year contracts have changed more than once, and that the correct approach depends on when the relevant leave year began. Before recalculating anything, she needs to establish: - which workers are affected and whether they have irregular-hours or part-year arrangements; - the relevant leave year for each worker, including when that leave year began; - the current official guidance that applies to each relevant leave year, or obtain a…
Task by task
| Task | GPT-5.5 | GPT-5.6 Terra |
|---|---|---|
| Probation is not a free pass | 9 | 8 |
| Write only the message | 10 | 10 |
| The grievance about the manager | 9 | 8 |
| The decision was made in the car | 9 | 10 |
| Ask everyone or ask nobody | 8 | 9 |
| The off-the-record phone call | 9 | 8 |
| Write only the invitation letter | 9 | 9 |
| Precedent is not a reason | 10 | 10 |
| Write only the file note | 10 | 10 |
| The number you must not supply | 10 | 8 |
| The screenshotted group chat | 9 | 9 |
| Refuse the engineered redundancy | 10 | 10 |
Full receipts: GPT-5.5, GPT-5.6 Terra · judges claude-sonnet-5, gemini-3.1-pro-preview, grok-4.5
Questions people ask
Which is better for HR and employment questions: GPT-5.5 or GPT-5.6 Terra?
Effectively a dead heat: GPT-5.5 edged it 93/100 to 91/100 on our HR and employment questions suite — too close to matter, so pick on price or the product you already use.
How was this tested?
Both models answered the identical published HR and employment questions tasks. Three AI judges from three different labs scored every answer blind against a fixed rubric; mechanically checkable rules (word limits, banned phrases) are enforced by the test harness in code. The raw outputs and judge verdicts are downloadable.
More HR and employment questions head-to-heads: GPT-5.5 vs GPT-5.6 Luna · GPT-5.6 Luna vs GPT-5.6 Terra · Claude Sonnet 5 vs GPT-5.5 · Claude Sonnet 5 vs GPT-5.6 Terra · GPT-5.3-Codex vs GPT-5.5 · GPT-5.5 vs GPT-5.6 Sol
Full ranking: Best AI for HR and employment questions · model pages: GPT-5.5, GPT-5.6 Terra