Class: RailsErrorDashboard::Services::LlmCostEstimator

Inherits:
Object
  • Object
show all
Defined in:
lib/rails_error_dashboard/services/llm_cost_estimator.rb

Overview

Estimates USD cost for an LLM call given provider, model, and token counts.

Prices are stored as USD per 1,000,000 tokens (the canonical unit used by OpenAI, Anthropic, and Google in their pricing pages).

IMPORTANT: This is a best-effort estimate using a hardcoded snapshot. Prices change frequently. Users SHOULD configure overrides via ‘config.llm_pricing_overrides` for production accuracy.

Returns nil for unknown models (no override AND not in the built-in table). Never raises — wrapped in rescue.

Constant Summary collapse

PRICES =

Prices last refreshed: 2026-05 (approximate, see provider pricing pages). Format: { “model-name” => { input: usd_per_1m, output: usd_per_1m } }

{
  # Anthropic
  "claude-opus-4-7" => { input: 15.0, output: 75.0 },
  "claude-sonnet-4-6" => { input: 3.0, output: 15.0 },
  "claude-haiku-4-5" => { input: 0.80, output: 4.0 },

  # OpenAI
  "gpt-4o" => { input: 2.50, output: 10.0 },
  "gpt-4o-mini" => { input: 0.15, output: 0.60 },
  "gpt-4-turbo" => { input: 10.0, output: 30.0 },
  "o1" => { input: 15.0, output: 60.0 },
  "o1-mini" => { input: 3.0, output: 12.0 },

  # Google
  "gemini-2.5-pro" => { input: 1.25, output: 5.0 },
  "gemini-2.5-flash" => { input: 0.075, output: 0.30 }
}.freeze

Class Method Summary collapse

Class Method Details

.estimate(provider:, model:, input_tokens:, output_tokens:) ⇒ Float?

Returns estimated USD cost, or nil if model unknown / tokens missing.

Parameters:

  • provider (String, Symbol) —

    currently informational only (not used in lookup)

  • model (String) —

    model identifier — matched case-insensitively against PRICES

  • input_tokens (Integer, nil)
  • output_tokens (Integer, nil)

Returns:

  • (Float, nil) —

    estimated USD cost, or nil if model unknown / tokens missing



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# File 'lib/rails_error_dashboard/services/llm_cost_estimator.rb', line 42

def self.estimate(provider:, model:, input_tokens:, output_tokens:)
  return nil if model.nil? || model.to_s.empty?
  return nil if input_tokens.nil? && output_tokens.nil?

  rate = lookup_rate(model.to_s)
  return nil unless rate

  in_tokens = input_tokens.to_i
  out_tokens = output_tokens.to_i

  cost = (in_tokens * rate[:input] + out_tokens * rate[:output]) / 1_000_000.0
  cost.round(6)
rescue
  nil
end