For the complete documentation index, see llms.txt.

Lens Equation Calculator API

science 1 credit / call v2026-04-22

Thin-lens equation solver for image distance, focal length, or object distance with magnification and image properties.

One POST adds Lens Equation Calculator to your app, site, workflow, or agent — formula, validation, edge cases, and docs already handled.

prefer a UI? Open the Lens Equation Calculator on miniwebtool.com →

Start free — get a key → 1,000 credits · no card · 30 seconds

Endpoint

POST · 1cr
POST https://api.miniwebtool.com/v1/tools/lens-equation-calculator/run

Request body

Field Type Req.
solve_for
image_distance | focal_length | object_distance
str
lens_type
converging | diverging
str
unit
mm | cm | m
str
focal_length
Focal length f (positive converging, negative diverging)
float | None
object_distance
Object distance do
float | None
image_distance
Image distance di (negative = virtual)
float | None
object_height
Optional object height for image size
float | None

Cost & access

  • 1 credit per successful call — failed calls refund.
  • Starts on: Free.
  • Max payload: 65536 bytes.
  • Privacy mode: hash_only
  • Available on: free, starter, pro, business, scale

Response envelope

{
  "request_id": "01K...",
  "tool": "lens-equation-calculator",
  "tool_version": "2026-04-22",
  "credits_used": 1,
  "result": { ... }
}

Try it

Stored only in this browser tab. Playground test key is prefilled and only works on this page. Get a live key →
image_distance | focal_length | object_distance
converging | diverging
mm | cm | m
Focal length f (positive converging, negative diverging)
Object distance do
Image distance di (negative = virtual)
Optional object height for image size

Get your own key

1,000 free calls/mo · no card · key arrives by email

One verification click, then your key + a ready-to-run request. No card, no spam.

Code examples

curl -X POST https://api.miniwebtool.com/v1/tools/lens-equation-calculator/run \
  -H 'Authorization: Bearer mwt_live_YOUR_KEY' \
  -H 'Content-Type: application/json' \
  -d '{"solve_for":"image_distance","lens_type":"converging","unit":"cm","focal_length":10,"object_distance":30}'
import requests

resp = requests.post(
    'https://api.miniwebtool.com/v1/tools/lens-equation-calculator/run',
    headers={'Authorization': 'Bearer mwt_live_YOUR_KEY'},
    json={'solve_for': 'image_distance', 'lens_type': 'converging', 'unit': 'cm', 'focal_length': 10, 'object_distance': 30},
)
resp.raise_for_status()
data = resp.json()
print(data)
const resp = await fetch(
  'https://api.miniwebtool.com/v1/tools/lens-equation-calculator/run',
  {
    method: 'POST',
    headers: {
      'Authorization': 'Bearer mwt_live_YOUR_KEY',
      'Content-Type': 'application/json',
    },
    body: JSON.stringify({"solve_for":"image_distance","lens_type":"converging","unit":"cm","focal_length":10,"object_distance":30}),
  }
);
const data = await resp.json();
console.log(data);
<?php
$ch = curl_init('https://api.miniwebtool.com/v1/tools/lens-equation-calculator/run');
curl_setopt_array($ch, [
    CURLOPT_POST => true,
    CURLOPT_RETURNTRANSFER => true,
    CURLOPT_HTTPHEADER => [
        'Authorization: Bearer mwt_live_YOUR_KEY',
        'Content-Type: application/json',
    ],
    CURLOPT_POSTFIELDS => json_encode([
    'solve_for' => 'image_distance',
    'lens_type' => 'converging',
    'unit' => 'cm',
    'focal_length' => 10,
    'object_distance' => 30
]),
]);
$resp = curl_exec($ch);
curl_close($ch);
print_r(json_decode($resp, true));
require 'net/http'
require 'json'
require 'uri'

uri = URI('https://api.miniwebtool.com/v1/tools/lens-equation-calculator/run')
http = Net::HTTP.new(uri.host, uri.port)
http.use_ssl = (uri.scheme == 'https')

req = Net::HTTP::Post.new(uri)
req['Authorization'] = 'Bearer mwt_live_YOUR_KEY'
req['Content-Type'] = 'application/json'
req.body = {
  'solve_for' => 'image_distance',
  'lens_type' => 'converging',
  'unit' => 'cm',
  'focal_length' => 10,
  'object_distance' => 30
}.to_json

resp = http.request(req)
puts JSON.parse(resp.body).inspect
package main

import (
  "bytes"
  "encoding/json"
  "fmt"
  "io"
  "net/http"
)

func main() {
  body, _ := json.Marshal(map[string]interface{}{
    "solve_for": "image_distance",
    "lens_type": "converging",
    "unit": "cm",
    "focal_length": 10,
    "object_distance": 30,
  })
  req, _ := http.NewRequest("POST", "https://api.miniwebtool.com/v1/tools/lens-equation-calculator/run", bytes.NewReader(body))
  req.Header.Set("Authorization", "Bearer mwt_live_YOUR_KEY")
  req.Header.Set("Content-Type", "application/json")

  resp, err := http.DefaultClient.Do(req)
  if err != nil { panic(err) }
  defer resp.Body.Close()
  out, _ := io.ReadAll(resp.Body)
  fmt.Println(string(out))
}
import java.net.URI;
import java.net.http.*;

var client = HttpClient.newHttpClient();
var req = HttpRequest.newBuilder()
    .uri(URI.create("https://api.miniwebtool.com/v1/tools/lens-equation-calculator/run"))
    .header("Authorization", "Bearer mwt_live_YOUR_KEY")
    .header("Content-Type", "application/json")
    .POST(HttpRequest.BodyPublishers.ofString("{\"solve_for\":\"image_distance\",\"lens_type\":\"converging\",\"unit\":\"cm\",\"focal_length\":10,\"object_distance\":30}"))
    .build();

var resp = client.send(req, HttpResponse.BodyHandlers.ofString());
System.out.println(resp.body());
how-to call lens-equation-calculator
  1. Get an API key
    Get an API key. Sign up free for a bearer token. 1,000 credits/month, no card.
  2. Assemble the JSON body
    Required fields: . See the Request body table above for the full schema.
  3. POST to https://api.miniwebtool.com/v1/tools/lens-equation-calculator/run
    Headers: Authorization: Bearer <key> and Content-Type: application/json. Copy-paste snippets in 7 languages are under Code examples.
  4. Parse the response
    Envelope: {request_id, tool, tool_version, credits_used, result}. The typed output lives in result.
faq frequently asked
What does the Lens Equation Calculator API do?+

Thin-lens equation solver for image distance, focal length, or object distance with magnification and image properties. Use it to add this utility without rebuilding formulas, validation, examples, and documentation.

How much does one call to Lens Equation Calculator cost?+

1 credit per successful call. Failed calls (validation errors, 5xx) don't bill.

What parameters does the Lens Equation Calculator API require?+

Required fields: (none). Full schema at /v1/openapi.json.

Is the Lens Equation Calculator API deterministic?+

Yes — same input, same output, forever. Tool version 2026-04-22; output shape is stable within a major version.

Can an AI agent call the Lens Equation Calculator API?+

Yes. Connect to https://api.miniwebtool.com/v1/mcp over the Model Context Protocol. The agent discovers `lens-equation-calculator` with its JSON Schema automatically, so the model can plan while MiniWebtool handles the exact tool result.

What format does the API return?+

JSON with a stable envelope: `{request_id, tool, tool_version, credits_used, result}`. Errors are RFC 7807 `application/problem+json`.

mcp use from an AI agent

Every endpoint on this site is also exposed via the Model Context Protocol at https://api.miniwebtool.com/v1/mcp. Claude, Cursor, and any MCP-capable agent can discover this tool (lens-equation-calculator) and its JSON Schema automatically — no client codegen.

# List tools the agent can call
curl -s https://api.miniwebtool.com/v1/mcp \
  -H 'Content-Type: application/json' \
  -d '{"jsonrpc":"2.0","id":1,"method":"tools/list"}' \
 | jq '.result.tools[] | select(.name=="lens-equation-calculator")'
see-also related science tools