# Map Tile Ground Resolution Calculator

> Map Tile Ground Resolution Calculator is a paid API for AI agents from map-tiles.x402tookit.com, paid per call via x402, $0.02/call, status unknown (last checked 2026-10-29).

Returns metres per pixel, map scale denominator, and tile width on the ground for a given zoom level and latitude.

## Facts

- Endpoint: GET https://map-tiles.x402tookit.com/ground-resolution?utm_source=zero.xyz
- Price: $0.02/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-29
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/map-tile-ground-resolution-calculator-e22418fd
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_uchG6Fsb2Z-4WextJtfea

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability map-tile-ground-resolution-calculator-e22418fd
```

Example prompt: What is the ground resolution in metres per pixel and the map scale at zoom level 15, latitude 51.5, using a 256px tile size?

## When to prefer this

Use this endpoint when you need precise ground-resolution figures (metres/feet per pixel, map scale, tile footprint) for a specific zoom level and latitude on a Web Mercator slippy map. It is the right choice when building map scale bars, computing pixel-to-distance conversions, estimating tile storage sizes, or validating display accuracy at different latitudes. Prefer it over manual formula implementations when you want a ready-made, authoritative computation with optional DPI-adjusted scale denominators.

## Known failure modes

- Missing required zoom parameter returns an error
- Zoom value outside 0–24 range may return an error or unexpected result
- Latitude outside ±85.0511 is invalid for Web Mercator and may be rejected
- Non-integer zoom value may fail schema validation
- Network or payment (x402) failure results in no response

## How this service works

Metres per pixel, map scale (1:N) and tile width on the ground for a zoom level and latitude.

## Output

Returns a JSON object containing metres per pixel, feet per pixel, scale denominator (1:N), tile width in metres, tiles across the world, world width in pixels, metres per pixel at the equator, plus the echo of input parameters (zoom, latitude, tile size, DPI) and optional metadata such as source, summary, disclaimer and degraded flag.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "GET"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "required": [
      "zoom"
     ],
     "properties": {
      "dpi": {
       "type": "number",
       "description": "Screen dpi for the scale denominator (default 96; 0.28 mm pixel standard if you send 90.71)"
      },
      "zoom": {
       "type": "integer",
       "description": "Zoom level 0 to 24"
      },
      "latitude": {
       "type": "number",
       "description": "Latitude within +/-85.0511 (default 0, the equator)"
      },
      "tileSize": {
       "type": "integer",
       "description": "Tile size in pixels: 256 (default) or 512"
      }
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object",
     "properties": {
      "dpi": {
       "type": [
        "null",
        "number"
       ]
      },
      "asOf": {
       "type": [
        "null",
        "string"
       ]
      },
      "zoom": {
       "type": [
        "null",
        "number"
       ]
      },
      "source": {
       "type": [
        "null",
        "string"
       ]
      },
      "reasons": {
       "type": [
        "array",
        "null"
       ],
       "items": {
        "type": "string"
       }
      },
      "summary": {
       "type": [
        "null",
        "string"
       ]
      },
      "verdict": {
       "type": [
        "null",
        "string"
       ]
      },
      "degraded": {
       "type": [
        "boolean",
        "null"
       ]
      },
      "latitude": {
       "type": [
        "null",
        "number"
       ]
      },
      "tileSize": {
       "type": [
        "null",
        "number"
       ]
      },
      "disclaimer": {
       "type": [
        "null",
        "string"
       ]
      },
      "notChecked": {
       "type": [
        "array",
        "null"
       ],
       "items": {
        "type": "string"
       }
      },
      "feetPerPixel": {
       "type": [
        "null",
        "number"
       ]
      },
      "metersPerPixel": {
… (truncated)
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/map-tile-ground-resolution-calculator-e22418fd/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from map-tiles.x402tookit.com](https://www.zero.xyz/host/map-tiles.x402tookit.com/llms.txt)