Image to Base64 Converter

Tool Overview

This tool converts an image file into a Base64-encoded string. You upload an image (by drag and drop or by clicking to choose a file). The tool reads the file and turns it into a data URI string (data:image/type;base64,...) and shows the raw Base64 part. You can copy the full data URI or only the Base64 part. So you get a text string you can use in HTML, CSS, or JSON.

Images are often embedded in web pages or API payloads as Base64 so that no separate file is needed. You have an image file and need the Base64 string. Doing it by hand is not practical. This tool takes your file and uses the browser to encode it. It checks the file type and size and the image dimensions. It shows the original image and a decoded preview so you can confirm the string is correct. So you can quickly get a string you can paste into code or config.

The tool is for developers and anyone who needs to embed images as Base64. You do not need to be an expert. You upload a file and copy the string. An optional Get Analysis button sends the image to a remote service and may return a description, alt text, and a suggested filename; that feature can fail and the main conversion does not depend on it.

Background & Concept Explanation

Base64 is a way to represent binary data as text. An image file is binary. When it is encoded in Base64 you get a long string of letters, digits, plus, and slash. That string can be used in HTML (for example in an img tag with a data URI), in CSS (for example in a background-image URL), or in JSON. A data URI starts with data:image/ followed by the type (for example png or jpeg), then ;base64, then the Base64 string. So the same string can be the full data URI or only the Base64 part after the comma. A related operation involves decoding Base64 images as part of a similar workflow.

This tool accepts one image file at a time. It uses the browser FileReader to read the file as a data URL. That gives you the full data:image/...;base64,... string. The tool then shows that string and lets you toggle whether to show the full data URI or only the Base64 part. It checks that the file is an image and that the format is supported. The supported formats are JPEG, PNG, GIF, WebP, and SVG. The file must be 10 MB or smaller and the image dimensions must be 5000 pixels or less per side. So the tool only processes valid, supported images within size limits.

People struggle when they encode by hand. They use the wrong tool or the wrong options. This tool does the encoding in the browser and shows both the original image and a preview from the Base64 string so you can confirm it matches. You can copy the full data URI for embedding or only the Base64 part for an API. So you get the right string for your use.

Key Features

• You upload an image by dragging and dropping it onto the upload area or by clicking to open a file picker. The area says Drop image here or click to browse. The tool accepts one file at a time. The accepted types are image files; the tool then checks that the format is JPEG, PNG, GIF, WebP, or SVG. So you can use drag and drop or the file dialog.
• The tool checks your file before encoding. The file must be an image (type starts with image/). It must be one of the supported formats. It must be 10 MB or smaller. It must not be empty. After encoding the tool loads the image to check its dimensions; width and height must be 5000 pixels or less. If any check fails the tool shows an error (for example Unsupported image format. Supported formats: JPEG, PNG, GIF, WebP, SVG or File size exceeds 10MB limit). So you know when to choose a different file.
• When the file is valid the tool shows two previews. The first is labeled Original and shows the image you uploaded with its file name and size. The second is labeled Decoded and shows the image from the Base64 string so you can confirm it matches. Both show the same image. So you can verify the encoding.
• The Base64 output is shown in a code-style box. The header shows the character count and an approximate decoded size (about 75% of the Base64 length in bytes). A checkbox labeled Data URI controls what is shown: when checked you see the full data URI (data:image/...;base64,...); when unchecked you see only the Base64 part after the comma. So you can copy the form you need.
• A Copy button copies the current output (full data URI or raw Base64) to the clipboard. So you can paste it into HTML, CSS, JSON, or another app.
• A Clear button removes the uploaded file and the result. The file input is reset so you can choose another file. So you can start over quickly.
• An optional Get Analysis button appears after you have a result. When you click it the tool sends the Base64 image and its MIME type to a remote service. The service may return a description of the image, a short alt text, and a suggested filename. These are shown in an Analysis section: Description, Alt Text (in quotes), and Suggested Filename with a copy button. If the request fails you see an error (for example Analysis failed. Please try again.). The main conversion does not depend on this. So you can try to get description and alt text when the service is available.

Common Use Cases

You need to embed a small image in an HTML email or a single HTML file. You upload the image. The tool shows the data URI. You leave the Data URI checkbox on and click Copy. You paste the string into the src of an img tag. So the image is inline and no separate file is needed. For adjacent tasks, converting to lowercase addresses a complementary step.

You are building an API that accepts Base64 image data. You upload the image. You uncheck Data URI so only the Base64 part is shown. You click Copy and paste the string into your request body or test tool. So you send only the Base64 part as required.

You want to use an image as a CSS background. You upload the image. You copy the full data URI. You paste it into your CSS as the URL in background-image. So the background is embedded without a separate file.

You want a description and alt text for the image. After the conversion you click Get Analysis. If the service responds you see Description, Alt Text, and Suggested Filename. You copy the alt text for your img alt attribute or the filename for saving. If the analysis fails you still have the Base64 string and can copy it. When working with related formats, converting to uppercase can be a useful part of the process.

The tool says Unsupported image format. You check that the file is JPEG, PNG, GIF, WebP, or SVG. You convert or export the image to one of these formats and try again.

The tool says the image dimensions exceed the maximum. Your image is over 5000 pixels in width or height. You resize it in another tool and upload again.

How to Use This Tool

1. Open the Image to Base64 Converter in your browser.
2. Upload an image. Drag and drop a file onto the upload area or click the area to open the file picker. Choose one image file. The file must be JPEG, PNG, GIF, WebP, or SVG and 10 MB or smaller.
3. Wait for the tool to process. It reads the file and encodes it as Base64. It then checks the image dimensions (max 5000 px per side). If anything fails you see an error message. If all checks pass you see two previews (Original and Decoded) and the Base64 output.
4. In the Base64 output area use the Data URI checkbox. When it is checked the box shows the full data URI (data:image/...;base64,...). When it is unchecked the box shows only the Base64 part. Use the one that matches where you will paste (for example full URI for HTML img src, raw Base64 for an API).
5. Click Copy to copy the current output (full URI or raw Base64) to the clipboard. Paste it into your HTML, CSS, JSON, or other app.
6. Click Clear to remove the file and result and choose another image. Optionally click Get Analysis to request a description, alt text, and suggested filename. If the service responds the Analysis section shows them and you can copy the suggested filename. If you see an error the main Base64 output is still correct.

Calculations & Logic

The tool reads your file with the browser FileReader using readAsDataURL. That method returns a string that starts with data:image/ followed by the MIME type (for example image/png), then ;base64, then a comma, then the Base64-encoded bytes. So the full string is a valid data URI. The tool stores that string and uses it as the preview URL and as the source for the decoded image check. In some workflows, converting text case is a relevant follow-up operation.

The tool builds an Image and sets its src to that data URI. When the image loads (onload) the tool reads its width and height. If either is over 5000 the tool shows an error and does not keep the result. If both are within limit the tool keeps the state and shows the output. So the result is only set when the image is valid and within the dimension limit.

The character count shown is the length of the string that is currently displayed (full data URI or Base64 part only). The approximate size in bytes is computed as the ceiling of that length times 0.75, because Base64 uses 4 characters for every 3 bytes. So you see how long the string is and roughly how big the decoded data is.

The supported formats are fixed in the tool: image/jpeg, image/jpg, image/png, image/gif, image/webp, image/svg+xml. Other image types (for example BMP) are rejected with Unsupported image format. So only these types are accepted. For related processing needs, converting temperatures handles a complementary task.

Reference Tables or Scales

Output can be copied as the full data URI (data:image/type;base64,...) or as the raw Base64 part only. The Data URI checkbox controls which form is shown and copied. Base64 encoding increases the text length; the decoded size is about 75% of the Base64 character count.

Tips, Limitations & Best Practices

Use a supported format. Only JPEG, PNG, GIF, WebP, and SVG are accepted. If your file is another type (for example BMP or HEIC) convert it to one of these first or use another tool.

Keep the file under 10 MB and the image under 5000 pixels per side. Very large files or dimensions trigger an error. Resize or compress the image elsewhere if you hit these limits.

Choose the right output form. For HTML img src or CSS url() use the full data URI and leave the checkbox on. For APIs that expect only Base64 turn the checkbox off and copy the raw part. Copy copies exactly what is shown in the box.

Base64 strings are longer than the binary file. A 1 MB image becomes about 1.33 MB of text. Large images produce very long strings that can be slow to paste or send. Prefer smaller images when you can.

Get Analysis is optional and can fail. You may see Analysis failed. Please try again. or AI analysis failed to produce valid output. The main encoding and copy always work when the file is valid. Do not rely on Analysis for critical steps.

Clear resets everything including the file input. After Clear you can upload a new file. Only one file is processed at a time; to encode another image clear first then upload again.