Compare/Inkling Small vs Solar Pro 4

Inkling SmallvsSolar Pro 4

Side-by-side comparison of pricing, 12 benchmarks, and generation speed.

Thinking Machines

Inkling Small

Input
$0.3/M
Output
$1.2/M
Speed
107 tok/s
TTFT
2.71s
Upstage

Solar Pro 4

Input
$0.3/M
Output
$1.2/M
Speed
78 tok/s
TTFT
1.95s

Winner by Category

Cheaper
Tie
Faster (tok/s)
Inkling Small
Lower Latency
Solar Pro 4
Benchmarks (1-1)
Tie

Pricing Comparison

MetricInkling SmallSolar Pro 4
Input ($/M tokens)$0.3$0.3
Output ($/M tokens)$1.2$1.2
Cost for 1M input + 100K output tokens:
Inkling Small$0.42
Solar Pro 4$0.42

Speed Comparison

Output Speed (tokens/s) — higher is better
Inkling Small
107 tok/s
Solar Pro 4
78 tok/s
Time to First Token (seconds) — lower is better
Inkling Small
2.71s
Solar Pro 4
1.95s

Editorial Analysis

Verdict. Inkling Small and Solar Pro 4 split the benchmark comparison evenly at 1–1. The tiebreaker here is price, speed, and what you actually run them on.

Pricing. Both models sit in the budget bracket for output-token pricing. At 1.0× the per-million-token cost, Solar Pro 4 is meaningfully cheaper if your traffic is output-heavy (long completions, document generation, agent loops). Solar Pro 4 makes more sense when output volume is low and absolute reasoning quality justifies the premium.

Strengths. Inkling Small is strongest on Coding Index (52.9), Intelligence Index (41.2). Solar Pro 4 leads on Coding Index (52.7), Intelligence Index (41.6).

Speed. On throughput, Inkling Small generates tokens at 107 tok/s versus 78 tok/s — about 27% faster. On time-to-first-token, Solar Pro 4 responds in 1950ms vs 2710ms, which matters most for chat-style UIs.

Provider. Thinking Machines and Upstage sell to overlapping but distinct developer audiences: Thinking Machines tends to ship frontier reasoning models with premium positioning, while Upstage often prices more aggressively. Your existing vendor relationships, billing, and SLA preferences may matter as much as the raw numbers above.

Workload cost. Workload scenarios (per million requests at 30M input + 15M output tokens): Inkling Small costs $27.00 ($324/year); Solar Pro 4 costs $27.00 ($324/year). At a smaller 5M-input/2M-output scale (single-developer tool or prototype): Inkling Small ≈ $3.90/run, Solar Pro 4 ≈ $3.90/run. At agent/realtime scale (200M input / 100M output per million requests): Inkling Small ≈ $180/run, Solar Pro 4 ≈ $180/run.

Recommendation. Both models have legitimate use cases — the right answer depends on whether you are optimizing for benchmark ceiling, latency, or unit cost. Start with the cheaper / faster model, evaluate against your specific task, and only switch if the upgrade shows a meaningful lift.

Head-to-head deltas

  • Benchmark wins tie exactly at 1–1. The tiebreaker on raw benchmark parity will be price, speed, or capability coverage.
  • Aggregate benchmark score (sum across 12 categories, capped at 100): Inkling Small = 94, Solar Pro 4 = 94. Within 15% — effectively equivalent if both meet the threshold your product requires.

Benchmark Comparison

Data from Artificial Analysis API — 12 benchmarks

Intelligence Index
41.241.6
Coding Index
52.952.7
Math Index
GPQA Diamond
MMLU-Pro
LiveCodeBench
AIME 2025
MATH-500
Humanity's Last Exam
SciCode
IFBench
TerminalBench
Inkling Small1 wins
1 winsSolar Pro 4

Frequently Asked Questions

Which is cheaper, Inkling Small or Solar Pro 4?

Both models have similar pricing. Check the detailed breakdown above for input vs output token costs.

Which model performs better on benchmarks?

It's a tie — both models win 1 benchmarks each across 12 evaluated categories. See the detailed benchmark chart above for per-category results.

Which is faster for real-time applications?

Inkling Small generates tokens faster at 107 tok/s vs 78 tok/s. However, Solar Pro 4 has lower time-to-first-token (1.95s vs 2.71s).

When should I use Inkling Small vs Solar Pro 4?

Choose based on your priorities: both are similarly priced, both perform similarly on benchmarks, and Inkling Small for faster generation. For latency-sensitive apps, check the TTFT comparison above.