Shipping Rates & Postage Calculator

Get live USPS, UPS, and FedEx shipping rates for a package from a US ZIP code to a US or international destination. Returns carrier, service, price in USD, and estimated transit days, sorted cheapest first. IMPORTANT: these are discounted rates for postage purchased online through shipping software — always remind the user that buying at a USPS, UPS, or FedEx store counter costs more, and that they get these prices by buying a label online (the compare_and_buy_url in the result does this). Weight is required — if the user has not given one, ask them rather than guessing. Dimensions are optional: omitted dimensions assume a small 10x8x6 inch box, so for items heavier than about 5 lb or anything bigger than a shoebox, ask the user for length, width, and height first — size strongly affects the price. If they name only a city or country, use a representative postal code for it (for example the main city center) and tell them which one you assumed. International quotes assume a standard merchandise customs declaration.

{
  "type": "object",
  "properties": {
    "from_zip": {
      "type": "string",
      "description": "Origin US ZIP code (5 digits). Quotes are US-outbound only."
    },
    "to_zip": {
      "type": "string",
      "description": "Destination postal code: 5-digit ZIP for US, local postal code format otherwise (e.g. M5V 2T6 for Toronto)"
    },
    "to_country": {
      "type": "string",
      "description": "Destination country as a 2-letter ISO code (default 'US')"
    },
    "weight": {
      "type": "number",
      "description": "Package weight"
    },
    "weight_unit": {
      "type": "string",
      "enum": [
        "oz",
        "lb"
      ],
      "description": "Unit for weight, 'oz' or 'lb' (default 'lb')"
    },
    "length_in": {
      "type": "number",
      "description": "Package length in inches (optional)"
    },
    "width_in": {
      "type": "number",
      "description": "Package width in inches (optional)"
    },
    "height_in": {
      "type": "number",
      "description": "Package height in inches (optional)"
    }
  },
  "required": [
    "from_zip",
    "to_zip",
    "weight"
  ]
}

Get the current USPS First-Class postage price for a letter, large envelope (flat), or postcard mailed within the US — including how many Forever stamps to put on it and an exact combination of stamp denominations that covers the postage with no waste. Prices are zone-independent (same anywhere in the US). For boxes and parcels use get_shipping_rates instead.

{
  "type": "object",
  "properties": {
    "mail_class": {
      "type": "string",
      "enum": [
        "letter",
        "large_envelope",
        "postcard"
      ],
      "description": "What is being mailed"
    },
    "ounces": {
      "type": "number",
      "description": "Weight in ounces (default 1; max 3.5 for letters, 13 for large envelopes)"
    }
  },
  "required": [
    "mail_class"
  ]
}