Kimi K2.5 vs GPT-5.2 Pro
Moonshot AIOpenAIboth via one key, provider price + 3%
Kimi K2.5 (Moonshot AI, released Jan 27, 2026) and GPT-5.2 Pro (OpenAI, Dec 10, 2025) sit at opposite ends of the price and evidence spectrum. Kimi K2.5 has 13 Design Arena rankings spanning agent and model categories, plus image input support, at provider prices of $0.375/$2.025 per million tokens. GPT-5.2 Pro has no published Design Arena or artificial_analysis benchmarks in this dataset, a 400K context window, mandatory reasoning, and provider prices of $21.00/$168.00 per million tokens. Both run on OpenKey with one API key and a flat 3% fee on provider list price.
Spec vs spec
| Spec | Kimi K2.5 | GPT-5.2 Pro |
|---|---|---|
| Context window | 262K | 400K |
| Max output | — | 128K |
| Input modalities | text, image | image, text, file |
| Output modalities | text | text |
| Released | Jan 27, 2026 | Dec 10, 2025 |
| Reasoning | optional | always on |
Pricing
Per 1M tokens. Provider price plus the flat 3% fee — the sum is what you pay.
moonshotai/kimi-k2.5
Input · 1M tokens
$0.375 + 3%$0.386
Output · 1M tokens
$2.02 + 3%$2.09
FEE — FLAT, EVERY MODEL3%
openai/gpt-5.2-pro
Input · 1M tokens
$21.00 + 3%$21.63
Output · 1M tokens
$168.00 + 3%$173.04
FEE — FLAT, EVERY MODEL3%
One workload, priced on both
10M input + 2M output tokens at each model's price, flat 3% fee included.
moonshotai/kimi-k2.5Cheaper
$8.03
$7.80 provider + 3%
openai/gpt-5.2-pro
$562.38
$546.00 provider + 3%
Pricing math on a real workload
Run 10M input tokens and 2M output tokens through each model. Kimi K2.5: provider price is $0.375/M input and $2.025/M output, giving $3.75 + $4.05 = $7.80 total. On OpenKey that's provider price × 1.03: $0.375 × 1.03 = $0.38625/M input and $2.025 × 1.03 = $2.08575/M output — the 3% fee adds about $0.23 to the $7.80 baseline. GPT-5.2 Pro: provider price is $21.00/M input and $168.00/M output, giving $546.00 total for the same workload — on OpenKey that's $21.63/M input and $173.04/M output after the 1.03 multiplier. That's a 70x cost gap (the input price ratio alone is 0.02, meaning Kimi's per-token input cost is roughly 2% of GPT-5.2 Pro's).
Coding and agent benchmarks
Kimi K2.5 has published Design Arena results across 13 categories. In the agents arena it ranks 2nd in Godot game dev (elo 1254, 59.5% win rate), 14th in fullstack (elo 1182, 54.2%), 15th in webapps (elo 1194, 50.3%), 17th in Android native (elo 1132, 57.8%), and 20th in mobile apps (elo 1186, 49.3%). In the models arena it ranks from 16th (website, elo 1291, 55.9% win rate) down to 25th (SVG, elo 1210, 50.2%), with codecategories at rank 20 (elo 1286, 54.7% win rate). GPT-5.2 Pro has no Design Arena or artificial_analysis benchmarks in this dataset, so there's no head-to-head score to cite — its description points to agentic coding and long-context improvements over GPT-5 Pro, but you'll need to test it directly against your own workload.
Context and long-document work
GPT-5.2 Pro's context window is 400,000 tokens against Kimi K2.5's 262,144 — a context ratio of 0.66, meaning Kimi holds about two-thirds of GPT-5.2 Pro's window. GPT-5.2 Pro also caps max completion at 128,000 tokens (Kimi has no stated max completion limit in this data) and accepts file inputs directly, which matters if you're feeding it PDFs or other documents rather than pasting text. For single-pass document review beyond 262K tokens, or workflows built around file uploads, GPT-5.2 Pro is the only option of the two.
Modality and reasoning controls
Kimi K2.5 takes text and image input and supports optional reasoning (on by default, not mandatory) alongside 19 other parameters including `top_k`, `min_p`, and `logprobs`. GPT-5.2 Pro takes text, image, and file input but only exposes 8 supported parameters, and reasoning is mandatory with a choice of medium, high, or xhigh effort (default: medium). If you need fine-grained sampling control or want reasoning off, Kimi K2.5 gives you that flexibility; GPT-5.2 Pro locks you into its reasoning pipeline.
Which model for which job
| Use case | Pick | Why |
|---|---|---|
| Web app UI generation | Kimi K2.5 | Ranks 15th in the Design Arena webapps agent category (elo 1194, 50.3% win rate) at a fraction of the cost. |
| Godot game dev prototyping | Kimi K2.5 | Ranks 2nd in the Design Arena Godot game dev category (elo 1254, 59.5% win rate). |
| Document analysis over 300K tokens | GPT-5.2 Pro | 400,000-token context window versus Kimi K2.5's 262,144. |
| High-volume batch processing | Kimi K2.5 | $7.80 vs $546.00 for a 10M-input/2M-output workload on OpenKey. |
| File-based workflows (PDF, docs) | GPT-5.2 Pro | Only one of the two with file input modality support. |
| Fine-grained sampling control | Kimi K2.5 | 19 supported parameters including top_k and min_p vs GPT-5.2 Pro's 8. |
Questions
- Which model is cheaper for high-volume use?
- Kimi K2.5, by a wide margin. A 10M-input/2M-output workload costs $7.80 on Kimi K2.5 versus $546.00 on GPT-5.2 Pro — the input price ratio is 0.02, so Kimi's input tokens cost about 2% of what GPT-5.2 Pro's do.
- Does Kimi K2.5 outperform GPT-5.2 Pro on coding benchmarks?
- Kimi K2.5 has 13 published Design Arena rankings (best: rank 2 in Godot game dev, elo 1254). GPT-5.2 Pro has no Design Arena or artificial_analysis benchmarks in this dataset, so a direct score comparison isn't possible — only Kimi's absolute numbers are documented here.
- Which model has the bigger context window?
- GPT-5.2 Pro, at 400,000 tokens versus Kimi K2.5's 262,144 tokens — a context ratio of 0.66. GPT-5.2 Pro also caps output at 128,000 tokens.
- Can I use both models through one API?
- Yes. Both Kimi K2.5 and GPT-5.2 Pro run on OpenKey with a single key, and pricing is the provider's list price plus a flat 3% fee — for example, Kimi K2.5's $0.375/M input becomes $0.38625/M on OpenKey.