I’m seeing significant discrepancies between the documented AI Gateway pricing and what’s actually being charged. I’ve done detailed analysis on two models and the numbers don’t add up.
Gemini 2.5 Pro
Documented pricing: $1.25/1M input, $10.00/1M output
Actual requests from my dashboard:

Back-calculating from the actual charges gives approximately $1.73/1M input and $43.74/1M output - significantly higher than documented, especially for output tokens (4.4x higher).
Request 1: 4900i + 46o = 0.01049125
Request 2: 3300i + 443o = 0.02508875
Solve for i from Request 1:
i = (0.01049125 - 46o) / 4900
Substitute into Request 2:
3300 × (0.01049125 - 46o) / 4900 + 443o = 0.02508875
Solve for o:
0.007068 - 30.98o + 443o = 0.02508875
412.02o = 0.018021
o = 0.0000437 per token = $43.74 per 1M output tokens
Plug o back in to get i:
i = (0.01049125 - 46 × 0.0000437) / 4900
i = 0.00848 / 4900
i = 0.00000173 per token = $1.73 per 1M input tokens
Verification
Using $1.73/1M input and $43.74/1M output:
Request 1: 4900 × $1.73/1M + 46 × $43.74/1M = $0.00848 + $0.00201 = $0.01049
Request 2: 3300 × $1.73/1M + 443 × $43.74/1M = $0.02509
Both match the actual charges.
I had similar results with gpt-5-mini. Not as extreme as this but they were still consistently wrong.