Command A Plus vs Mercury 2 vs Aion-3.0
Mercury 2 comes out ahead, 52 to 35 and 26 on our weighted score, and it is the cheaper option too.
CohereCommand A Plus
35/100- ECI—
- Price$2.50 / $10.00
- Context128K
- Our pick
InceptionMercury 2
52/100- ECI—
- Price$0.25 / $0.75
- Context128K
Aion Labs
Aion-3.0
26/100- ECI—
- Price$3.00 / $6.00
- Context131K
Mercury 2 is our pick
Mercury 2 is the better all-round choice, scoring 52/100 against Command A Plus (35) and Aion-3.0 (26). It leads on price. Command A Plus wins on inputs & features. The score weighs price 50%, inputs & features 30%, context window 20%. None of the shared benchmarks cover every model here yet, so capability is left out of this verdict.
- CapabilityNot enough dataNo independent benchmark covers every model here yet
- Lowest priceMercury 2Mercury 2 $0.375 · Aion-3.0 $3.75 · Command A Plus $4.38 per 1M tokens (3:1 blend)
- Longest contextAion-3.0Aion-3.0 131,072 · Command A Plus 128,000 · Mercury 2 128,000 tokens
- Widest inputsCommand A PlusCommand A Plus: Text, Images · Mercury 2: Text · Aion-3.0: Text
- Self-hostingCommand A PlusPublishes downloadable weights
| Measure | Weight | Command A Plus | Mercury 2 | Aion-3.0 |
|---|---|---|---|---|
| Price | 50% | 19 | 67 | 22 |
| Inputs & features | 30% | 70 | 45 | 35 |
| Context window | 20% | 24 | 24 | 25 |
| Overall | 100% | 35/100 | 52/100 | 26/100 |
Left out because at least one model lacks the data: capability. The remaining weights were rescaled.
Every spec in one table
Highlighted cells lead their row. Dashes mean the data is not published.
| Specification | Command A PlusCohere | Mercury 2Inception | Aion-3.0Aion Labs |
|---|---|---|---|
| Capability | |||
| Capabilities Index (ECI) | — | — | — |
| ECI rank | — | — | — |
| Price per million tokens | |||
| Input | $2.50 | $0.25 (best) | $3.00 |
| Output | $10.00 | $0.75 (best) | $6.00 |
| Cached input | — | $0.025 | — |
| Blended (3:1) | $4.38 | $0.375 (best) | $3.75 |
| Long-context rate | Same rate | Same rate | Same rate |
| Price source | Official Cohere API | Official Inception API | Median of 4 providers |
| Limits | |||
| Context window | 128,000 tokens | 128,000 tokens | 131,072 tokens (best) |
| Max output | 64,000 tokens (best) | 50,000 tokens | 32,768 tokens |
| Inputs and features | |||
| Text | Yes | Yes | Yes |
| Images | Yes | No | No |
| PDFs | No | No | No |
| Audio | No | No | No |
| Video | No | No | No |
| Reasoning | Yes | Yeslow · medium · high | Yes |
| Tool calling | Yes | Yes | Yes |
| Structured output | Yes | Yes | No |
| Availability | |||
| Weights | Open | Proprietary | Proprietary |
| API model ID | command-a-plus-05-2026 | mercury-2 | — |
| API providers | 3 | 7 (best) | 4 |
| Released | May 20, 2026 | Feb 24, 2026 | May 5, 2026 |
| Knowledge cutoff | Apr 1, 2025 | — | — |
What would a month cost?
Enter your expected volume in millions of tokens. List prices only; caching and batch discounts would lower these.
- Command A Plus$45.00
- Mercury 2$4.00
- Aion-3.0$42.00
Which should you choose?
Which is better: Command A Plus, Mercury 2 or Aion-3.0?
Mercury 2 is the better all-round choice, scoring 52/100 against Command A Plus (35) and Aion-3.0 (26). It leads on price. Command A Plus wins on inputs & features. The score weighs price 50%, inputs & features 30%, context window 20%. None of the shared benchmarks cover every model here yet, so capability is left out of this verdict.
Which is cheaper, Command A Plus, Mercury 2 or Aion-3.0?
Mercury 2 is cheaper at $0.25 input / $0.75 output per million tokens (official Inception API price). Aion-3.0 costs $3.00 input / $6.00 output per million tokens (median across 4 API providers); Command A Plus costs $2.50 input / $10.00 output per million tokens (official Cohere API price). At a typical mix of three input tokens to one output token, that is $0.375 per million tokens for Mercury 2 versus $3.75 for Aion-3.0 (10× as much) and $4.38 for Command A Plus (12× as much).
Which scores higher on benchmarks?
There is no independent benchmark that covers all three models yet. Command A Plus has not been scored yet, Mercury 2 has not been scored yet and Aion-3.0 has not been scored yet.
Which is better for coding?
There are no published SWE-bench Verified results for Command A Plus, Mercury 2 and Aion-3.0 yet, so there is no like-for-like coding score. Test both on a sample of your own tasks. All three support tool calling for agent workflows.
Which has the bigger context window?
Aion-3.0 has the largest context window at 131,072 tokens, against 128,000 for Command A Plus and 128,000 for Mercury 2. Maximum output per response: Command A Plus up to 64,000, Mercury 2 up to 50,000, Aion-3.0 up to 32,768 tokens.
Which can read images, PDFs, audio or video?
Command A Plus accepts text and images; Mercury 2 accepts text; Aion-3.0 accepts text. Command A Plus handles the widest range of inputs.
Are any of these open source?
Command A Plus publishes its weights and can be self-hosted; Mercury 2 and Aion-3.0 is proprietary.
Which is newer?
Command A Plus is the newest, released May 20, 2026. Aion-3.0 came out May 5, 2026; Mercury 2 came out Feb 24, 2026. Knowledge cutoff: Command A Plus Apr 1, 2025.
How do you decide the winner?
Each model gets a 0–100 score on capability (50%, independent benchmark results); price (25%, blended price per million tokens (3 input : 1 output), log scale); inputs & features (15%, image, PDF, audio and video input, tool calling, structured output and reasoning); context window (10%, maximum tokens per request, log scale). Dimensions missing for any model are dropped and the remaining weights rescaled, so every model is judged on the same evidence. Specs and prices come from public model listings and the labs’ own API pages; capability scores come from independent benchmark runs. Data updated Nov 2, 2026.
