Kimi K2.5vsLlama Nemotron Ultra 253B
Kimi K2.5 | Llama Nemotron Ultra 253B | |
|---|---|---|
| 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 | 253B |
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. | 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 | — |
Cheapest inputLowest input rate across third-party providers, excluding the lab itself. The cheapest endpoint may run a quantised build or a shorter context — see "Available from" on the model page. | $0.45DeepInfra | — |
Cheapest outputLowest output rate across third-party providers, excluding the lab itself. May come from a different provider than the cheapest input. | $2.25DeepInfra | — |
| Benchmarks | ||
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% | 66.3% |
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% | 76% |
| 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% | — |
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% | — |
| Overview | ||
| Company | Moonshot AI | NVIDIA |
| Release date | Jan 27 2026 | Apr 8 2025 |
| Access | Open Weight | Open Weight |
Other comparisons
Frequently asked questions
Kimi K2.5 leads Llama Nemotron Ultra 253B on 2 of the 2 benchmarks they both report (LiveCodeBench, GPQA Diamond). 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 Llama Nemotron Ultra 253B. Llama Nemotron Ultra 253B shipped 294 days before Kimi K2.5, so benchmark comparisons should account for the intervening progress.
Kimi K2.5 has 1T parameters, while Llama Nemotron Ultra 253B has 253B.
On LiveCodeBench, Kimi K2.5 leads at 85% vs Llama Nemotron Ultra 253B at 66.3%. On GPQA Diamond, Kimi K2.5 leads at 87.6% vs Llama Nemotron Ultra 253B at 76%.
Kimi K2.5 was released by Moonshot AI on Jan 27 2026.
Llama Nemotron Ultra 253B was released by NVIDIA on Apr 8 2025.
Kimi K2.5 leads on LiveCodeBench — Kimi K2.5 85% vs Llama Nemotron Ultra 253B 66.3%.
Kimi K2.5 leads on GPQA Diamond — Kimi K2.5 87.6% vs Llama Nemotron Ultra 253B 76%.
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 Llama Nemotron Ultra 253B. Rates are pay-as-you-go API prices verified on August 18, 2026.