Claude Instant 1.2vsKimi K2.5
Claude Instant 1.2 | Kimi K2.5 | |
|---|---|---|
| Specifications | ||
ParametersA rough measure of how big the model is. More parameters usually means more capable and more expensive to run, though it is a poor guide on its own — a smaller, newer model often beats a larger, older one. | — | 1T |
Context windowHow much text the model can hold in mind at once — your question, any documents you attach, the conversation so far, and its own reply. Go past it and the earliest part falls out of view. | 100k | 256k |
| API pricingUSD per 1M tokens · lower wins | ||
Input priceWhat you pay for everything you send the model — your question, plus any documents or earlier conversation you include with it. | — | $0.60 |
Output priceWhat you pay for the text the model writes back. It is normally the dearer half: producing an answer costs more than reading one. | — | $3.00 |
Cached input priceA reduced rate for text you send over and over. If every request starts with the same instructions or the same document, the provider keeps a copy ready and charges less to read it again. | — | $0.10 |
| BenchmarksPublished by one model only | ||
BullshitBench v2Nonsense detection — Given a confidently-worded but nonsensical prompt, does the AI spot that it makes no sense and push back — instead of playing along and inventing an answer? The score is how often it clearly called out the nonsense. Higher is better. | — | 52% |
SWE-Bench VerifiedCoding — Real coding tasks pulled from open-source projects — the AI has to find and fix actual bugs. A human-checked version of the original SWE-Bench. Higher is better. | — | 76.8% |
CursorBench v3.1Agentic coding — Cursor's own test of harder, real-world coding tasks inside a code editor. Higher is better. | — | 31.9% |
Next.js EvalsNext.js coding — Vercel's open eval of how well AI coding agents build and migrate real Next.js apps — measured as the share of tasks the agent completes successfully. Higher is better. | — | 21% |
LiveCodeBenchCompetitive coding — Coding problems published so recently the AI can't have seen them in training — a contamination-free test of raw programming skill. Higher is better. | — | 85% |
HumanEvalFunction synthesis — 164 small Python problems: the AI is given a function's description and has to write the working function. This was the coding benchmark of the GPT-3.5 and GPT-4 era, before the field moved to fixing real bugs in real repositories. Higher is better. | 58.7% | — |
GPQA DiamondScience — Graduate-level science questions in biology, physics, and chemistry — hard enough that subject-matter PhDs score around 65%. Higher is better. | — | 87.6% |
GSM8KGrade-school math — Grade-school maths word problems that take a few steps of arithmetic to work through. It separated the models of 2022 and 2023 sharply, then saturated. One caveat on the historical numbers: OpenAI included part of the GSM8K training set in GPT-4's pre-training mix, so GPT-4's score is not a clean few-shot result. Higher is better. | 86.7% | — |
Arena Elo (Code)Community preference (code) — Like the text arena, but people vote on which AI writes better code. The votes become a chess-style Elo rating on arena.ai. Higher is better. | — | 1433 |
| Overview | ||
| Company | Anthropic | Moonshot AI |
| Release date | Aug 9 2023 | Jan 27 2026 |
| Access | Proprietary | Open Weight |
Frequently asked questions
Claude Instant 1.2 and Kimi K2.5 don't publish scores on any of the same benchmarks, so there's no direct head-to-head comparison. Only Kimi K2.5 has a verified first-party API price: $0.60 per million input tokens and $3.00 per million output tokens. No pay-as-you-go API rate is tracked for Claude Instant 1.2. Claude Instant 1.2 shipped 902 days before Kimi K2.5, so benchmark comparisons should account for the intervening progress.
Context windows are 100k (Claude Instant 1.2) vs 256k (Kimi K2.5). Claude Instant 1.2 is proprietary, while Kimi K2.5 is open weight.
Direct benchmark comparisons are unavailable — Claude Instant 1.2 and Kimi K2.5 don't publish scores on any of the same benchmarks.
Claude Instant 1.2 was released by Anthropic on Aug 9 2023.
Kimi K2.5 was released by Moonshot AI on Jan 27 2026.
Only Kimi K2.5 has a verified first-party API price: $0.60 per million input tokens and $3.00 per million output tokens. No pay-as-you-go API rate is tracked for Claude Instant 1.2. Rates are pay-as-you-go API prices verified on August 18, 2026.
Claude Instant 1.2 has a 100k context window; Kimi K2.5 has 256k.
Claude Instant 1.2 is a proprietary model released by Anthropic. Kimi K2.5 is an open weight model released by Moonshot AI.