Arcee AI: AFM 4.5B

Text input Text output
Author's Description

AFM-4.5B is a 4.5 billion parameter instruction-tuned language model developed by Arcee AI. The model was pretrained on approximately 8 trillion tokens, including 6.5 trillion tokens of general data and 1.5 trillion tokens with an emphasis on mathematical reasoning and code generation.

Key Specifications
Cost
$$$
Context
65K
Parameters
5B
Released
Sep 16, 2025
Speed
Ability
Reliability
Supported Parameters

This model supports the following parameters:

Structured Outputs Stop Response Format Logit Bias Max Tokens Presence Penalty Frequency Penalty Min P Top P Temperature
Features

This model supports the following features:

Response Format Structured Outputs
Performance Summary

Arcee AI's AFM-4.5B is a 4.5 billion parameter instruction-tuned language model, pretrained on an extensive 8 trillion tokens with a focus on mathematical reasoning and code generation. The model consistently performs among the fastest models and offers highly competitive pricing across all evaluated benchmarks. It also demonstrates exceptional reliability with a 99% success rate, indicating minimal technical failures. In terms of performance across categories, AFM-4.5B exhibits a notable strength in General Knowledge, achieving 95.0% accuracy, placing it in the 43rd percentile. Its Hallucinations benchmark shows perfect accuracy at 0.0%, indicating a strong ability to acknowledge uncertainty. However, the model shows significant weaknesses in Instruction Following (22.7% accuracy, 27th percentile) and Reasoning (22.4% accuracy, 15th percentile), suggesting areas for improvement in complex multi-step tasks. Coding performance is moderate at 66.3% accuracy (29th percentile), despite its pretraining emphasis. Ethics performance is 91.0% (25th percentile), while Email Classification is 88.0% (13th percentile). The model's cost efficiency is generally good, with several benchmarks showing above-average cost percentiles.

Model Pricing

Current Pricing

Feature Price (per 1M tokens)
Prompt $0.1
Completion $0.4

Price History

Available Endpoints
Provider Endpoint Name Context Length Pricing (Input) Pricing (Output)
Together
Together | arcee-ai/afm-4.5b 65K $0.1 / 1M tokens $0.4 / 1M tokens
Benchmark Results
Benchmark Category Reasoning Strategy Free Executions Accuracy Cost Duration
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