Document understanding

Gemini models can process documents in PDF format, using native vision to understand entire document contexts. This goes beyond simple text extraction, allowing Gemini to:

  • Analyze and interpret content, including text, images, diagrams, charts, and tables, even in long documents up to 1000 pages.
  • Extract information into structured output formats.
  • Summarize and answer questions based on both the visual and textual elements in a document.
  • Transcribe document content (e.g. to HTML), preserving layouts and formatting, for use in downstream applications.

Passing PDF data inline

You can pass PDF data inline in the request to generateContent. This is best suited for smaller documents or temporary processing where you don't need to reference the file in subsequent requests. We recommend using the Files API for larger documents that you need to refer to in multi-turn interactions to improve request latency and reduce bandwidth usage.

The following example shows you how to fetch a PDF from a URL and convert it to bytes for processing:

Python

from google import genai from google.genai import types import httpx client = genai.Client() doc_url = "https://discovery.ucl.ac.uk/id/eprint/10089234/1/343019_3_art_0_py4t4l_convrt.pdf" # Retrieve and encode the PDF byte doc_data = httpx.get(doc_url).content prompt = "Summarize this document" response = client.models.generate_content( model="gemini-2.5-flash", contents=[ types.Part.from_bytes( data=doc_data, mime_type='application/pdf', ), prompt]) print(response.text) 

JavaScript

import { GoogleGenAI } from "@google/genai"; const ai = new GoogleGenAI({ apiKey: "GEMINI_API_KEY" }); async function main() {  const pdfResp = await fetch('https://discovery.ucl.ac.uk/id/eprint/10089234/1/343019_3_art_0_py4t4l_convrt.pdf')  .then((response) => response.arrayBuffer());  const contents = [  { text: "Summarize this document" },  {  inlineData: {  mimeType: 'application/pdf',  data: Buffer.from(pdfResp).toString("base64")  }  }  ];  const response = await ai.models.generateContent({  model: "gemini-2.5-flash",  contents: contents  });  console.log(response.text); } main(); 

Go

package main import (  "context"  "fmt"  "io"  "net/http"  "os"  "google.golang.org/genai" ) func main() {  ctx := context.Background()  client, _ := genai.NewClient(ctx, &genai.ClientConfig{  APIKey: os.Getenv("GEMINI_API_KEY"),  Backend: genai.BackendGeminiAPI,  })  pdfResp, _ := http.Get("https://discovery.ucl.ac.uk/id/eprint/10089234/1/343019_3_art_0_py4t4l_convrt.pdf")  var pdfBytes []byte  if pdfResp != nil && pdfResp.Body != nil {  pdfBytes, _ = io.ReadAll(pdfResp.Body)  pdfResp.Body.Close()  }  parts := []*genai.Part{  &genai.Part{  InlineData: &genai.Blob{  MIMEType: "application/pdf",  Data: pdfBytes,  },  },  genai.NewPartFromText("Summarize this document"),  }  contents := []*genai.Content{  genai.NewContentFromParts(parts, genai.RoleUser),  }  result, _ := client.Models.GenerateContent(  ctx,  "gemini-2.5-flash",  contents,  nil,  )  fmt.Println(result.Text()) } 

REST

DOC_URL="https://discovery.ucl.ac.uk/id/eprint/10089234/1/343019_3_art_0_py4t4l_convrt.pdf" PROMPT="Summarize this document" DISPLAY_NAME="base64_pdf" # Download the PDF wget -O "${DISPLAY_NAME}.pdf" "${DOC_URL}" # Check for FreeBSD base64 and set flags accordingly if [[ "$(base64 --version 2>&1)" = *"FreeBSD"* ]]; then  B64FLAGS="--input" else  B64FLAGS="-w0" fi # Base64 encode the PDF ENCODED_PDF=$(base64 $B64FLAGS "${DISPLAY_NAME}.pdf") # Generate content using the base64 encoded PDF curl "https://generativelanguage.googleapis.com/v1beta/models/gemini-2.5-flash:generateContent?key=$GOOGLE_API_KEY" \  -H 'Content-Type: application/json' \  -X POST \  -d '{  "contents": [{  "parts":[  {"inline_data": {"mime_type": "application/pdf", "data": "'"$ENCODED_PDF"'"}},  {"text": "'$PROMPT'"}  ]  }]  }' 2> /dev/null > response.json cat response.json echo jq ".candidates[].content.parts[].text" response.json # Clean up the downloaded PDF rm "${DISPLAY_NAME}.pdf" 

You can also read a PDF from a local file for processing:

Python

from google import genai from google.genai import types import pathlib client = genai.Client() # Retrieve and encode the PDF byte filepath = pathlib.Path('file.pdf') prompt = "Summarize this document" response = client.models.generate_content( model="gemini-2.5-flash", contents=[ types.Part.from_bytes( data=filepath.read_bytes(), mime_type='application/pdf', ), prompt]) print(response.text) 

JavaScript

import { GoogleGenAI } from "@google/genai"; import * as fs from 'fs'; const ai = new GoogleGenAI({ apiKey: "GEMINI_API_KEY" }); async function main() {  const contents = [  { text: "Summarize this document" },  {  inlineData: {  mimeType: 'application/pdf',  data: Buffer.from(fs.readFileSync("content/343019_3_art_0_py4t4l_convrt.pdf")).toString("base64")  }  }  ];  const response = await ai.models.generateContent({  model: "gemini-2.5-flash",  contents: contents  });  console.log(response.text); } main(); 

Go

package main import (  "context"  "fmt"  "os"  "google.golang.org/genai" ) func main() {  ctx := context.Background()  client, _ := genai.NewClient(ctx, &genai.ClientConfig{  APIKey: os.Getenv("GEMINI_API_KEY"),  Backend: genai.BackendGeminiAPI,  })  pdfBytes, _ := os.ReadFile("path/to/your/file.pdf")  parts := []*genai.Part{  &genai.Part{  InlineData: &genai.Blob{  MIMEType: "application/pdf",  Data: pdfBytes,  },  },  genai.NewPartFromText("Summarize this document"),  }  contents := []*genai.Content{  genai.NewContentFromParts(parts, genai.RoleUser),  }  result, _ := client.Models.GenerateContent(  ctx,  "gemini-2.5-flash",  contents,  nil,  )  fmt.Println(result.Text()) } 

Uploading PDFs using the Files API

We recommend you use Files API for larger files or when you intend to reuse a document across multiple requests. This improves request latency and reduces bandwidth usage by decoupling the file upload from the model requests.

Large PDFs from URLs

Use the File API to simplify uploading and processing large PDF files from URLs:

Python

from google import genai from google.genai import types import io import httpx client = genai.Client() long_context_pdf_path = "https://www.nasa.gov/wp-content/uploads/static/history/alsj/a17/A17_FlightPlan.pdf" # Retrieve and upload the PDF using the File API doc_io = io.BytesIO(httpx.get(long_context_pdf_path).content) sample_doc = client.files.upload( # You can pass a path or a file-like object here file=doc_io, config=dict( mime_type='application/pdf') ) prompt = "Summarize this document" response = client.models.generate_content( model="gemini-2.5-flash", contents=[sample_doc, prompt]) print(response.text) 

JavaScript

import { createPartFromUri, GoogleGenAI } from "@google/genai"; const ai = new GoogleGenAI({ apiKey: "GEMINI_API_KEY" }); async function main() {  const pdfBuffer = await fetch("https://www.nasa.gov/wp-content/uploads/static/history/alsj/a17/A17_FlightPlan.pdf")  .then((response) => response.arrayBuffer());  const fileBlob = new Blob([pdfBuffer], { type: 'application/pdf' });  const file = await ai.files.upload({  file: fileBlob,  config: {  displayName: 'A17_FlightPlan.pdf',  },  });  // Wait for the file to be processed.  let getFile = await ai.files.get({ name: file.name });  while (getFile.state === 'PROCESSING') {  getFile = await ai.files.get({ name: file.name });  console.log(`current file status: ${getFile.state}`);  console.log('File is still processing, retrying in 5 seconds');  await new Promise((resolve) => {  setTimeout(resolve, 5000);  });  }  if (file.state === 'FAILED') {  throw new Error('File processing failed.');  }  // Add the file to the contents.  const content = [  'Summarize this document',  ];  if (file.uri && file.mimeType) {  const fileContent = createPartFromUri(file.uri, file.mimeType);  content.push(fileContent);  }  const response = await ai.models.generateContent({  model: 'gemini-2.5-flash',  contents: content,  });  console.log(response.text); } main(); 

Go

package main import (  "context"  "fmt"  "io"  "net/http"  "os"  "google.golang.org/genai" ) func main() {  ctx := context.Background()  client, _ := genai.NewClient(ctx, &genai.ClientConfig{  APIKey: os.Getenv("GEMINI_API_KEY"),  Backend: genai.BackendGeminiAPI,  })  pdfURL := "https://www.nasa.gov/wp-content/uploads/static/history/alsj/a17/A17_FlightPlan.pdf"  localPdfPath := "A17_FlightPlan_downloaded.pdf"  respHttp, _ := http.Get(pdfURL)  defer respHttp.Body.Close()  outFile, _ := os.Create(localPdfPath)  defer outFile.Close()  _, _ = io.Copy(outFile, respHttp.Body)  uploadConfig := &genai.UploadFileConfig{MIMEType: "application/pdf"}  uploadedFile, _ := client.Files.UploadFromPath(ctx, localPdfPath, uploadConfig)  promptParts := []*genai.Part{  genai.NewPartFromURI(uploadedFile.URI, uploadedFile.MIMEType),  genai.NewPartFromText("Summarize this document"),  }  contents := []*genai.Content{  genai.NewContentFromParts(promptParts, genai.RoleUser), // Specify role  }  result, _ := client.Models.GenerateContent(  ctx,  "gemini-2.5-flash",  contents,  nil,  )  fmt.Println(result.Text()) } 

REST

PDF_PATH="https://www.nasa.gov/wp-content/uploads/static/history/alsj/a17/A17_FlightPlan.pdf" DISPLAY_NAME="A17_FlightPlan" PROMPT="Summarize this document" # Download the PDF from the provided URL wget -O "${DISPLAY_NAME}.pdf" "${PDF_PATH}" MIME_TYPE=$(file -b --mime-type "${DISPLAY_NAME}.pdf") NUM_BYTES=$(wc -c < "${DISPLAY_NAME}.pdf") echo "MIME_TYPE: ${MIME_TYPE}" echo "NUM_BYTES: ${NUM_BYTES}" tmp_header_file=upload-header.tmp # Initial resumable request defining metadata. # The upload url is in the response headers dump them to a file. curl "${BASE_URL}/upload/v1beta/files?key=${GOOGLE_API_KEY}" \  -D upload-header.tmp \  -H "X-Goog-Upload-Protocol: resumable" \  -H "X-Goog-Upload-Command: start" \  -H "X-Goog-Upload-Header-Content-Length: ${NUM_BYTES}" \  -H "X-Goog-Upload-Header-Content-Type: ${MIME_TYPE}" \  -H "Content-Type: application/json" \  -d "{'file': {'display_name': '${DISPLAY_NAME}'}}" 2> /dev/null upload_url=$(grep -i "x-goog-upload-url: " "${tmp_header_file}" | cut -d" " -f2 | tr -d "\r") rm "${tmp_header_file}" # Upload the actual bytes. curl "${upload_url}" \  -H "Content-Length: ${NUM_BYTES}" \  -H "X-Goog-Upload-Offset: 0" \  -H "X-Goog-Upload-Command: upload, finalize" \  --data-binary "@${DISPLAY_NAME}.pdf" 2> /dev/null > file_info.json file_uri=$(jq ".file.uri" file_info.json) echo "file_uri: ${file_uri}" # Now generate content using that file curl "https://generativelanguage.googleapis.com/v1beta/models/gemini-2.5-flash:generateContent?key=$GOOGLE_API_KEY" \  -H 'Content-Type: application/json' \  -X POST \  -d '{  "contents": [{  "parts":[  {"text": "'$PROMPT'"},  {"file_data":{"mime_type": "application/pdf", "file_uri": '$file_uri'}}]  }]  }' 2> /dev/null > response.json cat response.json echo jq ".candidates[].content.parts[].text" response.json # Clean up the downloaded PDF rm "${DISPLAY_NAME}.pdf" 

Large PDFs stored locally

Python

from google import genai from google.genai import types import pathlib import httpx client = genai.Client() # Retrieve and encode the PDF byte file_path = pathlib.Path('large_file.pdf') # Upload the PDF using the File API sample_file = client.files.upload( file=file_path, ) prompt="Summarize this document" response = client.models.generate_content( model="gemini-2.5-flash", contents=[sample_file, "Summarize this document"]) print(response.text) 

JavaScript

import { createPartFromUri, GoogleGenAI } from "@google/genai"; const ai = new GoogleGenAI({ apiKey: "GEMINI_API_KEY" }); async function main() {  const file = await ai.files.upload({  file: 'path-to-localfile.pdf'  config: {  displayName: 'A17_FlightPlan.pdf',  },  });  // Wait for the file to be processed.  let getFile = await ai.files.get({ name: file.name });  while (getFile.state === 'PROCESSING') {  getFile = await ai.files.get({ name: file.name });  console.log(`current file status: ${getFile.state}`);  console.log('File is still processing, retrying in 5 seconds');  await new Promise((resolve) => {  setTimeout(resolve, 5000);  });  }  if (file.state === 'FAILED') {  throw new Error('File processing failed.');  }  // Add the file to the contents.  const content = [  'Summarize this document',  ];  if (file.uri && file.mimeType) {  const fileContent = createPartFromUri(file.uri, file.mimeType);  content.push(fileContent);  }  const response = await ai.models.generateContent({  model: 'gemini-2.5-flash',  contents: content,  });  console.log(response.text); } main(); 

Go

package main import (  "context"  "fmt"  "os"  "google.golang.org/genai" ) func main() {  ctx := context.Background()  client, _ := genai.NewClient(ctx, &genai.ClientConfig{  APIKey: os.Getenv("GEMINI_API_KEY"),  Backend: genai.BackendGeminiAPI,  })  localPdfPath := "/path/to/file.pdf"  uploadConfig := &genai.UploadFileConfig{MIMEType: "application/pdf"}  uploadedFile, _ := client.Files.UploadFromPath(ctx, localPdfPath, uploadConfig)  promptParts := []*genai.Part{  genai.NewPartFromURI(uploadedFile.URI, uploadedFile.MIMEType),  genai.NewPartFromText("Give me a summary of this pdf file."),  }  contents := []*genai.Content{  genai.NewContentFromParts(promptParts, genai.RoleUser),  }  result, _ := client.Models.GenerateContent(  ctx,  "gemini-2.5-flash",  contents,  nil,  )  fmt.Println(result.Text()) } 

REST

NUM_BYTES=$(wc -c < "${PDF_PATH}") DISPLAY_NAME=TEXT tmp_header_file=upload-header.tmp # Initial resumable request defining metadata. # The upload url is in the response headers dump them to a file. curl "${BASE_URL}/upload/v1beta/files?key=${GEMINI_API_KEY}" \  -D upload-header.tmp \  -H "X-Goog-Upload-Protocol: resumable" \  -H "X-Goog-Upload-Command: start" \  -H "X-Goog-Upload-Header-Content-Length: ${NUM_BYTES}" \  -H "X-Goog-Upload-Header-Content-Type: application/pdf" \  -H "Content-Type: application/json" \  -d "{'file': {'display_name': '${DISPLAY_NAME}'}}" 2> /dev/null upload_url=$(grep -i "x-goog-upload-url: " "${tmp_header_file}" | cut -d" " -f2 | tr -d "\r") rm "${tmp_header_file}" # Upload the actual bytes. curl "${upload_url}" \  -H "Content-Length: ${NUM_BYTES}" \  -H "X-Goog-Upload-Offset: 0" \  -H "X-Goog-Upload-Command: upload, finalize" \  --data-binary "@${PDF_PATH}" 2> /dev/null > file_info.json file_uri=$(jq ".file.uri" file_info.json) echo file_uri=$file_uri # Now generate content using that file curl "https://generativelanguage.googleapis.com/v1beta/models/gemini-2.5-flash:generateContent?key=$GOOGLE_API_KEY" \  -H 'Content-Type: application/json' \  -X POST \  -d '{  "contents": [{  "parts":[  {"text": "Can you add a few more lines to this poem?"},  {"file_data":{"mime_type": "application/pdf", "file_uri": '$file_uri'}}]  }]  }' 2> /dev/null > response.json cat response.json echo jq ".candidates[].content.parts[].text" response.json 

You can verify the API successfully stored the uploaded file and get its metadata by calling files.get. Only the name (and by extension, the uri) are unique.

Python

from google import genai import pathlib client = genai.Client() fpath = pathlib.Path('example.txt') fpath.write_text('hello') file = client.files.upload(file='example.txt') file_info = client.files.get(name=file.name) print(file_info.model_dump_json(indent=4)) 

REST

name=$(jq ".file.name" file_info.json) # Get the file of interest to check state curl https://generativelanguage.googleapis.com/v1beta/files/$name > file_info.json # Print some information about the file you got name=$(jq ".file.name" file_info.json) echo name=$name file_uri=$(jq ".file.uri" file_info.json) echo file_uri=$file_uri 

Passing multiple PDFs

The Gemini API is capable of processing multiple PDF documents (up to 1000 pages) in a single request, as long as the combined size of the documents and the text prompt stays within the model's context window.

Python

from google import genai import io import httpx client = genai.Client() doc_url_1 = "https://arxiv.org/pdf/2312.11805" doc_url_2 = "https://arxiv.org/pdf/2403.05530" # Retrieve and upload both PDFs using the File API doc_data_1 = io.BytesIO(httpx.get(doc_url_1).content) doc_data_2 = io.BytesIO(httpx.get(doc_url_2).content) sample_pdf_1 = client.files.upload( file=doc_data_1, config=dict(mime_type='application/pdf') ) sample_pdf_2 = client.files.upload( file=doc_data_2, config=dict(mime_type='application/pdf') ) prompt = "What is the difference between each of the main benchmarks between these two papers? Output these in a table." response = client.models.generate_content( model="gemini-2.5-flash", contents=[sample_pdf_1, sample_pdf_2, prompt]) print(response.text) 

JavaScript

import { createPartFromUri, GoogleGenAI } from "@google/genai"; const ai = new GoogleGenAI({ apiKey: "GEMINI_API_KEY" }); async function uploadRemotePDF(url, displayName) {  const pdfBuffer = await fetch(url)  .then((response) => response.arrayBuffer());  const fileBlob = new Blob([pdfBuffer], { type: 'application/pdf' });  const file = await ai.files.upload({  file: fileBlob,  config: {  displayName: displayName,  },  });  // Wait for the file to be processed.  let getFile = await ai.files.get({ name: file.name });  while (getFile.state === 'PROCESSING') {  getFile = await ai.files.get({ name: file.name });  console.log(`current file status: ${getFile.state}`);  console.log('File is still processing, retrying in 5 seconds');  await new Promise((resolve) => {  setTimeout(resolve, 5000);  });  }  if (file.state === 'FAILED') {  throw new Error('File processing failed.');  }  return file; } async function main() {  const content = [  'What is the difference between each of the main benchmarks between these two papers? Output these in a table.',  ];  let file1 = await uploadRemotePDF("https://arxiv.org/pdf/2312.11805", "PDF 1")  if (file1.uri && file1.mimeType) {  const fileContent = createPartFromUri(file1.uri, file1.mimeType);  content.push(fileContent);  }  let file2 = await uploadRemotePDF("https://arxiv.org/pdf/2403.05530", "PDF 2")  if (file2.uri && file2.mimeType) {  const fileContent = createPartFromUri(file2.uri, file2.mimeType);  content.push(fileContent);  }  const response = await ai.models.generateContent({  model: 'gemini-2.5-flash',  contents: content,  });  console.log(response.text); } main(); 

Go

package main import (  "context"  "fmt"  "io"  "net/http"  "os"  "google.golang.org/genai" ) func main() {  ctx := context.Background()  client, _ := genai.NewClient(ctx, &genai.ClientConfig{  APIKey: os.Getenv("GEMINI_API_KEY"),  Backend: genai.BackendGeminiAPI,  })  docUrl1 := "https://arxiv.org/pdf/2312.11805"  docUrl2 := "https://arxiv.org/pdf/2403.05530"  localPath1 := "doc1_downloaded.pdf"  localPath2 := "doc2_downloaded.pdf"  respHttp1, _ := http.Get(docUrl1)  defer respHttp1.Body.Close()  outFile1, _ := os.Create(localPath1)  _, _ = io.Copy(outFile1, respHttp1.Body)  outFile1.Close()  respHttp2, _ := http.Get(docUrl2)  defer respHttp2.Body.Close()  outFile2, _ := os.Create(localPath2)  _, _ = io.Copy(outFile2, respHttp2.Body)  outFile2.Close()  uploadConfig1 := &genai.UploadFileConfig{MIMEType: "application/pdf"}  uploadedFile1, _ := client.Files.UploadFromPath(ctx, localPath1, uploadConfig1)  uploadConfig2 := &genai.UploadFileConfig{MIMEType: "application/pdf"}  uploadedFile2, _ := client.Files.UploadFromPath(ctx, localPath2, uploadConfig2)  promptParts := []*genai.Part{  genai.NewPartFromURI(uploadedFile1.URI, uploadedFile1.MIMEType),  genai.NewPartFromURI(uploadedFile2.URI, uploadedFile2.MIMEType),  genai.NewPartFromText("What is the difference between each of the " +  "main benchmarks between these two papers? " +  "Output these in a table."),  }  contents := []*genai.Content{  genai.NewContentFromParts(promptParts, genai.RoleUser),  }  modelName := "gemini-2.5-flash"  result, _ := client.Models.GenerateContent(  ctx,  modelName,  contents,  nil,  )  fmt.Println(result.Text()) } 

REST

DOC_URL_1="https://arxiv.org/pdf/2312.11805" DOC_URL_2="https://arxiv.org/pdf/2403.05530" DISPLAY_NAME_1="Gemini_paper" DISPLAY_NAME_2="Gemini_1.5_paper" PROMPT="What is the difference between each of the main benchmarks between these two papers? Output these in a table." # Function to download and upload a PDF upload_pdf() {  local doc_url="$1"  local display_name="$2"  # Download the PDF  wget -O "${display_name}.pdf" "${doc_url}"  local MIME_TYPE=$(file -b --mime-type "${display_name}.pdf")  local NUM_BYTES=$(wc -c < "${display_name}.pdf")  echo "MIME_TYPE: ${MIME_TYPE}"  echo "NUM_BYTES: ${NUM_BYTES}"  local tmp_header_file=upload-header.tmp  # Initial resumable request  curl "${BASE_URL}/upload/v1beta/files?key=${GOOGLE_API_KEY}" \  -D "${tmp_header_file}" \  -H "X-Goog-Upload-Protocol: resumable" \  -H "X-Goog-Upload-Command: start" \  -H "X-Goog-Upload-Header-Content-Length: ${NUM_BYTES}" \  -H "X-Goog-Upload-Header-Content-Type: ${MIME_TYPE}" \  -H "Content-Type: application/json" \  -d "{'file': {'display_name': '${display_name}'}}" 2> /dev/null  local upload_url=$(grep -i "x-goog-upload-url: " "${tmp_header_file}" | cut -d" " -f2 | tr -d "\r")  rm "${tmp_header_file}"  # Upload the PDF  curl "${upload_url}" \  -H "Content-Length: ${NUM_BYTES}" \  -H "X-Goog-Upload-Offset: 0" \  -H "X-Goog-Upload-Command: upload, finalize" \  --data-binary "@${display_name}.pdf" 2> /dev/null > "file_info_${display_name}.json"  local file_uri=$(jq ".file.uri" "file_info_${display_name}.json")  echo "file_uri for ${display_name}: ${file_uri}"  # Clean up the downloaded PDF  rm "${display_name}.pdf"  echo "${file_uri}" } # Upload the first PDF file_uri_1=$(upload_pdf "${DOC_URL_1}" "${DISPLAY_NAME_1}") # Upload the second PDF file_uri_2=$(upload_pdf "${DOC_URL_2}" "${DISPLAY_NAME_2}") # Now generate content using both files curl "https://generativelanguage.googleapis.com/v1beta/models/gemini-2.5-flash:generateContent?key=$GOOGLE_API_KEY" \  -H 'Content-Type: application/json' \  -X POST \  -d '{  "contents": [{  "parts":[  {"file_data": {"mime_type": "application/pdf", "file_uri": '$file_uri_1'}},  {"file_data": {"mime_type": "application/pdf", "file_uri": '$file_uri_2'}},  {"text": "'$PROMPT'"}  ]  }]  }' 2> /dev/null > response.json cat response.json echo jq ".candidates[].content.parts[].text" response.json 

Technical details

Gemini supports a maximum of 1,000 document pages. Each document page is equivalent to 258 tokens.

While there are no specific limits to the number of pixels in a document besides the model's context window, larger pages are scaled down to a maximum resolution of 3072x3072 while preserving their original aspect ratio, while smaller pages are scaled up to 768x768 pixels. There is no cost reduction for pages at lower sizes, other than bandwidth, or performance improvement for pages at higher resolution.

Gemini 3 models

Gemini 3 introduces granular control over multimodal vision processing with the media_resolution parameter. You can now set the resolution to low, medium, or high per individual media part. With this addition, the processing of PDF documents has been updated:

  1. Native text inclusion: Text natively embedded in the PDF is extracted and provided to the model.
  2. Billing & token reporting:
    • You are not charged for tokens originating from the extracted native text in PDFs.
    • In the usage_metadata section of the API response, tokens generated from processing PDF pages (as images) are now counted under the IMAGE modality, not a separate DOCUMENT modality as in some earlier versions.

For more details about the media resolution parameter, see the Media resolution guide.

Document types

Technically, you can pass other MIME types for document understanding, like TXT, Markdown, HTML, XML, etc. However, document vision only meaningfully understands PDFs. Other types will be extracted as pure text, and the model won't be able to interpret what we see in the rendering of those files. Any file-type specifics like charts, diagrams, HTML tags, Markdown formatting, etc., will be lost.

Best practices

For best results:

  • Rotate pages to the correct orientation before uploading.
  • Avoid blurry pages.
  • If using a single page, place the text prompt after the page.

What's next

To learn more, see the following resources:

  • File prompting strategies: The Gemini API supports prompting with text, image, audio, and video data, also known as multimodal prompting.
  • System instructions: System instructions let you steer the behavior of the model based on your specific needs and use cases.