Best-value AI model API
Scored 92/100 on our 30-task general suite — level on quality with 2 others (Grok 4.5, GPT-5.6 Terra) — the top spot goes on the tie-break: cleanest rule-compliance, then lowest measured cost. Free to use via chat.z.ai.
GLM 5.2 is the engine inside Z Chat. Go to chat.z.ai ↗ — free to use. Not fussed about the last point or two? Any of the top 3 here will serve you well.
For anyone building on AI, the question is capability per pound. We score each model on the same 30-task general suite and put the score beside its live per-million-token price — which for some models moves during the day, because OpenRouter blends prices across providers. Where a price is volatile we say so.
updated 11 Aug 2026 · tested by Robert Prime · re-ranks automatically when a new run lands
- All 9 sat the identical 30-task suite — same tasks, same order, one attempt each.
- Every answer marked blind: judges are not told which entrant wrote it.
- Three judges per answer, each from a competing lab. A panel never includes the entrant's own lab.
- Scored 0–10 against a fixed rubric. Answers breaking a task's explicit rules are capped by machine, not by opinion.
- Ties broken by fewest rule breaches, then lowest measured cost — published, not editorial.
- Nobody pays for placement. Last computed 11 Aug 2026.
Every score below links to the raw file behind it: every task, the entrant’s real answer, and all three judges’ marks.
| # | Model | Our score |
|---|---|---|
| 1 | GLM 5.2latest | 92/100 |
| 2 | Grok 4.5latest | 92/100 |
| 3 | GPT-5.6 Terralatest | 92/100 |
| 4 | Kimi K3 | 90/100 |
| 5 | Gemini 3.5 Flash | 89/100 |
| 6 | DeepSeek V4 Pro | 88/100 |
| 7 | Gemini 3.1 Pro Preview | 86/100 |
| 8 | DeepSeek V4 Flash | 85/100 |
| 9 | Claude Opus 4.6 | 83/100 |
“API cost” is what software developers pay to build on a model — ignore it if you just use the website. Each model answers each task once. Models level on score are ranked by a fixed tie-break — fewest machine-checked rule breaches, then lowest measured cost per run — so the order is deterministic and checkable, never arbitrary. Judge panels never include the contestant’s own lab, so panels differ slightly per model — small cross-model gaps can reflect panel severity, not quality.
Made by Z.ai — their newest model. You use it inside Z Chat — nothing to install; free via chat.z.ai.
Strongest showing: “Medium generation” — scored 10/10 by the panel. Weakest: “Explain code” at 6/10. On 3 tasks a judge flagged a possible instruction breach — advisory only: the machine check did not confirm it and the panel outvoted it.
“The response flawlessly incorporates all required details into a warm, engaging narrative. It perfectly hits the 150-word constraint (counting hyphenated words as single words) and is highly suitable for a business website.”— google/gemini-3.1-pro-preview, judging blind · full receipts ↓
30 tasks · 11 Aug 2026 · judges claude-sonnet-5, gemini-3.1-pro-preview, gpt-5.6-terra · API $0.966 in / $3.036 out per 1M tokens · free via chat.z.ai ↗ (checked 11 Aug 2026) · full model page →
Made by xAI — their newest model. You use it inside Grok — nothing to install; free via grok.com.
Strongest showing: “Contact details” — scored 10/10 by the panel. Weakest: “Forbidden words” at 7/10. On 3 tasks a judge flagged a possible instruction breach — advisory only: the machine check did not confirm it and the panel outvoted it.
“The response perfectly follows the instructions, accurately extracting all four individuals and formatting them exactly as requested, correctly using 'unknown' where the organisation is not specified.”— google/gemini-3.1-pro-preview, judging blind · full receipts ↓
30 tasks · 11 Aug 2026 · judges claude-sonnet-5, gemini-3.1-pro-preview, gpt-5.6-terra · API $2 in / $6 out per 1M tokens · free via grok.com ↗ (checked 11 Aug 2026) · full model page →
Made by OpenAI — their newest model. You use it inside ChatGPT — nothing to install.
Strongest showing: “Medium generation” — scored 10/10 by the panel. Weakest: “Product description” at 5/10. On 5 tasks a judge flagged a possible instruction breach — advisory only: the machine check did not confirm it and the panel outvoted it.
“Flawless response. It includes all requested details in an inviting, professional tone and hits the exact 150-word constraint perfectly.”— google/gemini-3.1-pro-preview, judging blind · full receipts ↓
30 tasks · 11 Aug 2026 · judges claude-sonnet-5, gemini-3.1-pro-preview, grok-4.5 · API $2 in / $12 out per 1M tokens · full model page →
See it for yourself
One task from the suite, and what the leader, the middle of the table and the bottom actually wrote. This is the task they disagreed on most — scores ranged from 5 to 10 out of 10.
Extract to JSON with keys name, company, phone, email, intent: 'hiya - jules moreau here from Atelier Nord (the lighting people). best number is 07700 900 457, or jules@ateliernord.fr. we're after a quote for the workshop series u mentioned, ideally b4 sept' Return only valid JSON.
{
"name": "Jules Moreau",
"company": "Atelier Nord",
"phone": "07700 900 457",
"email": "jules@ateliernord.fr",
"intent": "Quote for workshop series before September"
}Judge: The response perfectly extracts all requested information into a valid JSON format with the exact keys specified, and includes no extra text.
```json
{
"name": "Jules Moreau",
"company": "Atelier Nord",
"phone": "07700 900 457",
"email": "jules@ateliernord.fr",
"intent": "Requesting a quote for the workshop series, ideally before September"
}
```Judge: Accurate extraction, correct JSON structure, all fields properly filled; minor code fence wrapper not pure JSON.
```json
{
"name": "Jules Moreau",
"company": "Atelier Nord",
"phone": "07700 900 457",
"email": "jules@ateliernord.fr",
"intent": "Requesting a quote for the workshop series before September"
}
```Judge: Accurately extracted all requested fields into the correct JSON keys. However, it violates the 'only valid JSON' constraint by including markdown code block formatting.
Trimmed to fit. Every full answer, every judge’s score: GLM 5.2, Gemini 3.5 Flash, Claude Opus 4.6
How this ranking is made
Every model answers the identical published task suite. Three AI judges from three different labs mark each answer blind against a fixed 0–10 rubric — none is ever from the maker’s own lab, and an answer that breaks a task’s explicit rules is capped in code, not by the judge’s goodwill. The score is the average, out of 100.
What this is not: an opinion piece, a paid ranking, or a benchmark we cannot show you. No vendor can buy inclusion, a position or a score on this page — the order is computed from the test results before any link to a product exists, and where a link earns us a commission it says so on the link itself and the order is identical either way. Every score links its raw outputs and judge verdicts. The full protocol · How we make money · receipts: GLM 5.2, Grok 4.5, GPT-5.6 Terra, Kimi K3, Gemini 3.5 Flash, DeepSeek V4 Pro, Gemini 3.1 Pro Preview, DeepSeek V4 Flash, Claude Opus 4.6
Questions people ask
What is the best-value AI model API in 2026?
GLM 5.2 leads our tested ranking with 92/100 on our 30-task general suite, in a dead heat with Grok 4.5 (92). Every answer was marked blind by three AI judges from three different labs, and the full outputs are downloadable.
How is this ranking made?
Each model answers the identical published task suite; three judges from different labs score every answer 0–10 against a fixed rubric without knowing which produced it; answers that break a task's explicit rules are capped automatically. The score is the average, out of 100. No vendor pays for placement.
What happens when two models score the same?
They are separated by a fixed, published tie-break rather than by editorial choice: first the fewest machine-checked rule breaches, then the lowest measured cost per run. The order is therefore reproducible from the same data, and where the tie-break decides the top place the page says so.
How often does this page update?
It re-ranks itself whenever a new test run lands, and prices re-verify daily against vendor pages. The current ranking was last computed on 11 Aug 2026.
Is GLM 5.2 free?
Yes — GLM 5.2 can be used at no cost via chat.z.ai, confirmed on 11 Aug 2026.
Head-to-head battles
Worth knowing: Kimi K3 finished ahead of GPT-5.6 Terra head-to-head despite ranking below it above; Grok 4.5 finished ahead of GLM 5.2 head-to-head despite ranking below it above. The ranking scores each one alone against a fixed rubric; a battle puts them on the same task and asks which answer is better. When a gap this small flips, the honest read is that they are hard to separate — not that one of the numbers is wrong.
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