Celeris-1 vs K2-Horizon-0.9B
Wins 3 of 5 areas
Coding · Reasoning · Long documents
Wins 1 of 5 areas
Agents
Celeris-1 is the stronger all-rounder.K2-Horizon-0.9B is better at agents.
Scores updated · 12 tests both models report · How we compare
Where each one wins
Tests won in each of the five areas where both have results. Each piece is one test, so a longer bar means more evidence; grey means the two scored within a point of each other.
- ReasoningHard problems that need careful thinking20Celeris-12 of 3 tests · 1 tie
- CodingWriting and fixing software10Celeris-11 of 1 test
- Long documentsFinding answers in very long texts10Celeris-11 of 1 test
- AgentsCarrying out multi-step tasks on its own01K2-Horizon-0.9B1 of 3 tests · 2 ties
- FactsGetting facts right instead of making them up11Even1 each
Coding and long documents rest on a single test each.
What it costs
Prices per million tokens, roughly 750,000 words. The bars show the cost of a million tokens read plus a million written.
The biggest differences
The tests each model wins by the widest margin, up to three each. Scores are out of 100.
Where Celeris-1 pulls ahead
- Graduate-level biology, physics and chemistry questionsGPQA Diamond+33.8points ahead
- Reasons across sets of long documentsAA-LCR+31.7points ahead
- Code for real scientific research problemsSciCode+14.7points ahead
Where K2-Horizon-0.9B pulls ahead
- Avoids making up answers it doesn't knowAA-Omniscience · Non-hallucination+7.1points ahead
- Customer-service tasks in a simulated bankτ-Bench V3 · Banking+1points ahead
Every test, side by side
All 12 tests both models report. The winning score is in its model's colour; marks a score checked independently.
AgentsK2-Horizon-0.9B
- τ-Bench V3 · BankingK2-Horizon-0.9B by 13.94.9+1
- GDPValtie00tie
- Terminal-Bench 4.0tie00tie
ReasoningCeleris-1
- GPQA DiamondCeleris-1 by 33.863.129.3+33.8
- Humanity's Last ExamCeleris-1 by 1.46.85.4+1.4
- CritPttie00tie
FactsEven
- AA-Omniscience · Non-hallucinationK2-Horizon-0.9B by 7.17.214.3+7.1
- AA-Omniscience · AccuracyCeleris-1 by 4.1116.9+4.1
Other results2 tests, not counted
Tests outside the eight areas. They are not counted above: several are summary scores built from other tests, or the same test under another name.
- AA IntelligenceCeleris-1 by 3.36.33+3.3
- AA-OmniscienceCeleris-1 by 1.2-71.6-72.8+1.2
Questions people ask
Which is better, Celeris-1 or K2-Horizon-0.9B?
Celeris-1 wins three of the five areas where both have results: coding, reasoning and long documents. K2-Horizon-0.9B wins agents. They are level on facts.
Which is better for coding?
Celeris-1. It wins the one coding test both models report.
How do you compare the two?
We use the 12 benchmark tests both models have published scores on. The verdict counts the 10 tests in the eight capability areas, and a gap under one point (ten on rating-style scales) counts as a tie. The other 2 are listed but not counted, because several are summary scores or repeat a test. Each score is the one shown on the model's own page.