AI task costs · in pounds

What it costs to summarise a 50-page PDF with AI

gpt-oss-120b is the cheapest of the 24 models priced, at 2.2p for 20 PDFs a month (0.11p per PDF). The dearest, GPT-6 Astra, costs £5.88; the middle of the range is Mistral Large 4 at 38p.

How much does it cost to summarise a long PDF report with ChatGPT, Claude or Gemini through their APIs? The answer below covers price only, not quality.

Prices of from OpenRouter's public API price list · converted at the ECB reference rate of ($1 = £0.7538) · Urbano DX

Cost by model, cheapest first

The workload

  • A 50-page PDF of about 500 words a page: 25,000 words of text.
  • About 0.75 English words per token: 33,300 tokens of document text, plus 700 tokens of instructions. 34,000 input tokens in one request.
  • A summary of about 750 words: 1,000 output tokens.
  • No prompt cache: every PDF is different.
  • 20 PDFs a month, about one each working day.
Summarise a 50-page PDF: cost by model in pounds
ModelPer PDF20 PDFs a monthRate used (USD)
gpt-oss-120bOpenAI0.11p2.2p$0.037 in, $0.17 out per 1M tokens
DeepSeek V4.1 FlashDeepSeek0.12p2.4p$0.02016 in, $0.891 out per 1M tokens
Gemma 4 31BGoogle0.26p5.1p$0.09 in, $0.34 out per 1M tokens
Claude Haiku 5.5Anthropic0.29p5.9p$0.10 in, $0.50 out per 1M tokens
GPT-6 LunaOpenAI0.29p5.9p$0.10 in, $0.50 out per 1M tokens
Qwen3.8 FlashQwen0.42p8.4p$0.15 in, $0.47 out per 1M tokens
Mistral Small 4Mistral0.43p8.6p$0.15 in, $0.60 out per 1M tokens
Gemini 2.5 FlashGoogle0.96p19p$0.30 in, $2.50 out per 1M tokens
Gemini 3.5 Flash LiteGoogle0.96p19p$0.30 in, $2.50 out per 1M tokens
GPT-4.1 MiniOpenAI1.1p23p$0.40 in, $1.60 out per 1M tokens
Llama 3.3 70B InstructMeta1.6p31p$0.59 in, $0.79 out per 1M tokens
Mistral Large 4Mistral1.9p38p$0.68 in, $2.09 out per 1M tokens
Gemini 3.8 FlashGoogle2.2p44p$0.75 in, $3.75 out per 1M tokens
DeepSeek V4 Pro 0423DeepSeek2.6p52p$0.9553 in, $1.911 out per 1M tokens
Claude Haiku 4.5Anthropic2.9p59p$1.00 in, $5.00 out per 1M tokens
Muse Spark 1.3Meta3.5p70p$1.25 in, $4.25 out per 1M tokens
Grok 4.7SpaceXAI5.6p£1.12$2.00 in, $6.00 out per 1M tokens
Qwen3.8 Max (0902)Qwen5.6p£1.12$2.00 in, $6.00 out per 1M tokens
Claude Sonnet 5.5Anthropic5.9p£1.18$2.00 in, $10.00 out per 1M tokens
Gemini 4 ArgonGoogle5.9p£1.18$2.00 in, $10.00 out per 1M tokens
GPT-6.1 SolOpenAI5.9p£1.18$2.00 in, $10.00 out per 1M tokens
Claude Opus 5.5Anthropic12p£2.35$4.00 in, $20.00 out per 1M tokens
Claude Fable 5.1Anthropic29p£5.88$10.00 in, $50.00 out per 1M tokens
GPT-6 AstraOpenAI29p£5.88$10.00 in, $50.00 out per 1M tokens

How the numbers are worked out

  • Each workload is written out on its page: tokens in and out, the share read from a prompt cache, audio minutes or images. Cost = workload × the model's listed rate, so you can check any figure with a calculator.
  • Rates are OpenRouter's API prices in our snapshot of , the same ones on our model pricing pages. Buying from the developer directly can cost a little more or less. When rates move, the price change log records it.
  • US dollars become pounds at the European Central Bank reference rate of : €1 = $1.1195 = £0.84385, so $1 = £0.7538. VAT, card fees and top-up fees are not included.
  • About 0.75 English words make one token. Each model's tokenizer counts the same text a little differently, so treat a figure as a close estimate, not a quote.
  • Models that reason before answering can add thinking tokens, billed as output. These figures count none, so a model with thinking switched on can cost more.
  • This compares price only. It says nothing about which model does the job well: a cheap model that gets a tenth of the answers wrong can cost more in staff time than it saves.

Other tasks

All ten tasks side by side

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