AI task costs · in pounds

What it costs to write 500 product descriptions with AI

gpt-oss-120b is the cheapest of the 24 models priced, at 2.7p for 500 descriptions a month (0.0054p per description). The dearest, GPT-6 Astra, costs £7.54; the middle of the range is Mistral Large 4 at 41p.

How much does it cost to write product descriptions for an online shop with an AI model? 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

  • 800 tokens of instructions and brand style guide, plus 200 tokens of product facts: 1,000 input tokens.
  • A description of about 150 words: 200 output tokens.
  • 500 descriptions a month, written one per request with no prompt cache.
Write 500 product descriptions: cost by model in pounds
ModelPer description500 descriptions a monthRate used (USD)
gpt-oss-120bOpenAI0.0054p2.7p$0.037 in, $0.17 out per 1M tokens
Gemma 4 31BGoogle0.012p6p$0.09 in, $0.34 out per 1M tokens
DeepSeek V4.1 FlashDeepSeek0.015p7.5p$0.02016 in, $0.891 out per 1M tokens
Claude Haiku 5.5Anthropic0.015p7.5p$0.10 in, $0.50 out per 1M tokens
GPT-6 LunaOpenAI0.015p7.5p$0.10 in, $0.50 out per 1M tokens
Qwen3.8 FlashQwen0.018p9.2p$0.15 in, $0.47 out per 1M tokens
Mistral Small 4Mistral0.02p10p$0.15 in, $0.60 out per 1M tokens
GPT-4.1 MiniOpenAI0.054p27p$0.40 in, $1.60 out per 1M tokens
Llama 3.3 70B InstructMeta0.056p28p$0.59 in, $0.79 out per 1M tokens
Gemini 2.5 FlashGoogle0.06p30p$0.30 in, $2.50 out per 1M tokens
Gemini 3.5 Flash LiteGoogle0.06p30p$0.30 in, $2.50 out per 1M tokens
Mistral Large 4Mistral0.083p41p$0.68 in, $2.09 out per 1M tokens
DeepSeek V4 Pro 0423DeepSeek0.1p50p$0.9553 in, $1.911 out per 1M tokens
Gemini 3.8 FlashGoogle0.11p57p$0.75 in, $3.75 out per 1M tokens
Claude Haiku 4.5Anthropic0.15p75p$1.00 in, $5.00 out per 1M tokens
Muse Spark 1.3Meta0.16p79p$1.25 in, $4.25 out per 1M tokens
Grok 4.7SpaceXAI0.24p£1.21$2.00 in, $6.00 out per 1M tokens
Qwen3.8 Max (0902)Qwen0.24p£1.21$2.00 in, $6.00 out per 1M tokens
Claude Sonnet 5.5Anthropic0.3p£1.51$2.00 in, $10.00 out per 1M tokens
Gemini 4 ArgonGoogle0.3p£1.51$2.00 in, $10.00 out per 1M tokens
GPT-6.1 SolOpenAI0.3p£1.51$2.00 in, $10.00 out per 1M tokens
Claude Opus 5.5Anthropic0.6p£3.02$4.00 in, $20.00 out per 1M tokens
Claude Fable 5.1Anthropic1.5p£7.54$10.00 in, $50.00 out per 1M tokens
GPT-6 AstraOpenAI1.5p£7.54$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

Want this running on your own data, with the cost measured? See the fixed-price AI pilot