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Free tool · #6

LLM Cost Spike Simulator

Project how your monthly bill moves when traffic, prompt size, or output length grows — and see which lever drives it.

Prices verified 15 Jul 2026 · 131 models

Today’s monthly usage

701 models
20M tokens
5M tokens

Growth scenario

3×
1.5×
1×

Projected change

+$275.00/mo (+275%)

$100.00$375.00 · openai · gpt-4o

  • Now$100.00
  • Projected$375.00

What drives it — each lever on its own

  • Traffic 3×+$200.00
  • Prompt size 1.5×+$25.00
  • Output length 1×+$0
Use this tool from code — or hand it to your agentagent prompt · REST · MCP

Hand this tool to your coding agent

Paste into Claude Code, Cursor, Codex, or any agent. It learns to call this tool over REST or MCP, reaches for it when you ask, and keeps our sourced/pending labels honest.

You can use telemeter.ai's free "LLM Cost Spike Simulator" — a keyless, read-only tool (no signup), available as an HTTP API and an MCP tool. What it does: Project how your monthly bill moves when traffic, prompt size, or output length grows — and see which lever drives it.

Whenever I ask you something this tool answers, call it and use its result instead of estimating yourself.

REST:
  curl -sX POST https://telemeter.ai/api/tools/cost-spike-simulator -H 'content-type: application/json' -d '{"model":"gpt-4o","baselineInputTokens":1000000,"baselineOutputTokens":200000,"trafficMultiplier":3,"promptMultiplier":1,"outputMultiplier":1}'

MCP: the telemeter MCP server at https://telemeter.ai/mcp exposes this as the tool "cost-spike-simulator" — call it with tools/call.

The response is JSON: { status, data, summary, provenance }. "provenance" carries the source and the date the figure was verified. If status is "pending" or "stale", tell me the value isn't currently verified rather than presenting it as fact.

Or call it directly. This tool runs behind one handler with three front doors — this page, a REST endpoint, and an MCP tool. Same result, read-only, no key. The example below is a request that works.

REST
curl -sX POST https://telemeter.ai/api/tools/cost-spike-simulator \
  -H 'content-type: application/json' \
  -d '{"model":"gpt-4o","baselineInputTokens":1000000,"baselineOutputTokens":200000,"trafficMultiplier":3,"promptMultiplier":1,"outputMultiplier":1}'
MCP — tools/call at https://telemeter.ai/mcp
curl -sX POST https://telemeter.ai/mcp \
  -H 'content-type: application/json' \
  -d '{"jsonrpc":"2.0","id":1,"method":"tools/call","params":{"name":"cost-spike-simulator","arguments":{"model":"gpt-4o","baselineInputTokens":1000000,"baselineOutputTokens":200000,"trafficMultiplier":3,"promptMultiplier":1,"outputMultiplier":1}}}'
Input schema (JSON Schema)
{
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "type": "object",
  "properties": {
    "model": {
      "type": "string",
      "minLength": 1
    },
    "baselineInputTokens": {
      "type": "integer",
      "minimum": 0,
      "maximum": 100000000000
    },
    "baselineOutputTokens": {
      "type": "integer",
      "minimum": 0,
      "maximum": 100000000000
    },
    "trafficMultiplier": {
      "default": 1,
      "type": "number",
      "minimum": 0,
      "maximum": 10000
    },
    "promptMultiplier": {
      "default": 1,
      "type": "number",
      "minimum": 0,
      "maximum": 10000
    },
    "outputMultiplier": {
      "default": 1,
      "type": "number",
      "minimum": 0,
      "maximum": 10000
    }
  },
  "required": [
    "model",
    "baselineInputTokens",
    "baselineOutputTokens",
    "trafficMultiplier",
    "promptMultiplier",
    "outputMultiplier"
  ],
  "additionalProperties": false
}

Want this across your whole stack?

Telemeter tracks real cost, latency, and quality on every production agent run — on the same verified pricing behind this tool.

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