text model comparison
Mercury 2.5 vs Mercury 3
Mercury 2.5 and Mercury 3 are both current text models, from Inception. Both cost $0.20 per 1M input tokens. Mercury 3 has the larger context window, 1,000,000 vs 260,000 tokens.
- Longer context window
- Mercury 31M tokens against 260K tokens
- Newer release
- Mercury 3Oct 2026 against Sep 2026
Data verified October 23, 2026 · Dataset 2026-10-23
Side by side
Mercury 2.5 and Mercury 3, line by line
Prices in effect today, compared at the same tier wherever both list one. The better value in each row is highlighted.
| Fact | Mercury 2.5 | Mercury 3 |
|---|---|---|
| Price | ||
| Price per 1M input tokens | $0.20 | $0.20 |
| Price per 1M output tokens | $0.75 | $0.70 (better) |
| Specs | ||
| Provider | Inception | Inception |
| Release date | September 8, 2026 | October 19, 2026 |
| Access | API only | API only |
| Context window | 260,000 tokens | 1,000,000 tokens |
| Max output | 65,536 tokens | 131,072 tokens |
| Input | text | text |
| Output | text | text |
Charts
Against every current text model
Where Mercury 2.5 and Mercury 3 land among the current models of their task, on every independent benchmark, on price and on context.
Where each stands
No independent benchmark has scored either model yet, so the tiles rank their prices among the current models of their task.
Price and context
Price per 1M input tokens
Mercury 2.5:#7of 49
$0.20 · cheaper than 83%
Mercury 3:#7of 49
$0.20 · cheaper than 83%
Price per 1M output tokens
Mercury 2.5:#8of 49
$0.75 · cheaper than 85%
Mercury 3:#7of 49
$0.70 · cheaper than 88%
Context window
Mercury 2.5:#57of 64
260K tokens · longer than 11%
Mercury 3:#26of 64
1M tokens · longer than 22%
Cost
What each costs
Example workloads at each provider's listed rates, then every other rate either one lists. The cheaper figure in each row is highlighted.
The same work, priced
For 10M input and 2M output tokens, Mercury 2.5 costs 1.0 times as much as Mercury 3, at each provider's listed rates.
10M input and 2M output tokens
Mercury 2.5 costs 1.0× as much
- Mercury 2.5
- $3.50
- Mercury 3
- $3.40
The same, with 9M of the input tokens cached
Mercury 2.5 costs 1.1× as much
- Mercury 2.5
- $1.88
- Mercury 3
- $1.78
| Workload or rate | Mercury 2.5 | Mercury 3 |
|---|---|---|
| Example workloads | ||
| 10M input and 2M output tokens | $3.50 | $3.40 (better) |
| The same, with 9M of the input tokens cached | $1.88 | $1.78 (better) |
| Other listed rates | ||
| 1M input tokens, cached | $0.02 | $0.02 |
Verdict
When to choose each
Mercury 2.5
Where it leads
No measured lead over Mercury 3 in this data.
Best for
- Latency-critical agent loops and voice agents
- High-throughput, low-cost text generation
Watch out for
- Inception publishes no benchmark scores for it, and no independent score is recorded here
- The recorded rates are list prices; an 80% launch discount was running with no published end date
Mercury 3
Where it leads
- Lower price per 1M output tokens, $0.70 vs $0.75
- Larger context window 1,000,000 vs 260,000 tokens
- Longer responses, up to 131,072 vs 65,536 output tokens
Best for
- Latency-critical agent loops and real-time search agents
- High-volume text generation at low cost
Watch out for
- The recorded rates are list prices; a 50% launch discount was running with no published end date
- Inception comparisons are its own, and no independent benchmark score is recorded here yet
From benchmark to production
Building on Mercury 2.5 or Mercury 3?
Public scores rarely hold on your own data. We test both models on your real tasks, then build the agent or pipeline around the one that wins.
FAQ
Mercury 2.5 vs Mercury 3 FAQ
Which is cheaper, Mercury 2.5 or Mercury 3?
Both cost $0.20 per 1M input tokens. For 10M input and 2M output tokens, Mercury 2.5 costs $3.50 and Mercury 3 $3.40 at standard rates.
Which is cheaper with prompt caching, Mercury 2.5 or Mercury 3?
Mercury 2.5 charges $0.02 per 1M cached input tokens, 90% below its standard input rate, and Mercury 3 $0.02, 90% below. With 9M of 10M input tokens cached and 2M output tokens, Mercury 2.5 costs $1.88 and Mercury 3 $1.78.
Which has the larger context window, Mercury 2.5 or Mercury 3?
Mercury 3 has the larger context window, 1,000,000 vs 260,000 tokens. Mercury 3 returns up to 131,072 tokens per response, Mercury 2.5 65,536.
Further reading
More on Mercury 2.5 and Mercury 3
Production evaluation
Choosing between Mercury 2.5 and Mercury 3?
Public benchmarks narrow the shortlist. We run both on your own tasks, data and cost limits, then build the routing and review controls to run the winner in production.
- A head-to-head evaluation on your real workload
- Routing between models by cost and difficulty