How do I decode Base64 online?

Switch to Decode mode on the ToolDekho Base64 encoder, then paste your Base64 string. The decoded text appears immediately in the output panel. A red error message appears if the input is not valid Base64. Base64 strings typically end with one or two equals signs as padding characters.

Does Base64 work with Hindi and Indian language text?

Yes, provided a UTF-8 wrapper is applied before Base64 conversion. UTF-8 covers all Unicode characters, including Devanagari, Tamil, Bengali, Telugu, and every other Indian script. Standard Base64 without the UTF-8 wrapper fails for characters outside the Latin range. ToolDekho's encoder applies this wrapper automatically.

What is Base64 used for in web development?

Base64 is used to embed images directly in HTML and CSS as data URIs, avoiding a separate HTTP request. Email attachments are Base64-encoded for transmission over SMTP. JWT tokens use Base64 URL encoding for the header and payload sections. API keys and credentials are also Base64-encoded in HTTP Basic Authentication headers.

Is Base64 the same as encryption?

No. Base64 is encoding, not encryption. Anyone with a Base64 string can decode it back to the original text in seconds. Do not use Base64 to protect sensitive data. For secure storage or transmission of secrets, use AES encryption or TLS.

How do I decode a JWT token payload?

Copy the middle section of the JWT (between the first and second dots). Base64 URL encoding uses - instead of + and _ instead of /. Replace - with + and _ with / in the segment. Then paste it into a Base64 decoder to read the JSON claims, including user ID, roles, and expiry time.

Base64 Encoding for API Integration: A Dev Guide

Q: What is Base64 encoding?

Base64 is a binary-to-text encoding scheme that represents data using 64 printable ASCII characters: A–Z, a–z, 0–9, plus, and slash. Every 3 bytes of input become 4 characters. Output is always about 33% larger than the input. Base64 is used to transport binary data safely over text-based systems — not to encrypt it.

Q: Why does my Base64 output end with == ?

Base64 works in groups of 3 bytes. When the input length is not a multiple of 3, padding characters (=) are added to complete the final group. One = means 1 byte of padding was added. Two == means 2 bytes were added. Seeing == at the end is normal and expected — removing it breaks strict decoders.

Over 80% of modern web APIs transmit credentials or tokens using Base64 encoding. Base64 encoding converts binary data into plain ASCII text, so it travels safely across systems designed for text only.

What Is Base64 Encoding?

Base64 is a binary-to-text encoding scheme. Every 3 bytes of input become 4 printable ASCII characters drawn from A–Z, a–z, 0–9, +, and /. Output is always about 33% larger than the input.

Base64 does not encrypt data. Anyone holding a Base64 string can decode it in seconds. The purpose is safe transport, not secrecy.

Why Base64 Encoding Matters for API Integration

Indian developers often build on platforms like Razorpay, Cashfree, or Aadhaar-based verification APIs. All three involve Base64 encoding in at least one common place.

HTTP Basic Authentication

HTTP Basic Auth sends credentials as username:password encoded in Base64 inside the Authorization header. The server decodes the header on arrival. Without Base64 encoding, special characters in passwords can corrupt the header.

Picture a developer at a Bengaluru startup who integrates a payment gateway late one Friday. The API keeps returning 401 Unauthorized. After an hour of frustration, the culprit turns out to be an @ symbol in the password. Base64 encoding the credentials correctly fixes the call immediately.

JWT Token Payloads

A JWT (JSON Web Token) has three sections separated by dots. The header and payload sections are Base64 URL-encoded JSON objects. The third section is a cryptographic signature.

Decoding the middle segment of a JWT reveals the claims: user ID, roles, and token expiry. No external library is needed. Paste the segment into a decoder to inspect it directly.

Base64 URL encoding differs slightly from standard Base64. The + character becomes - and the / character becomes _. Padding = characters are also removed. To decode a JWT segment, replace - with + and _ with / before decoding.

Embedding Images as Data URIs

Front-end developers embed small icons and logos directly in CSS or HTML as Base64-encoded data URIs. A data URI looks like:

data:image/png;base64,iVBORw0KGgo...

Embedding the image eliminates a separate HTTP request. For high-traffic Indian e-commerce sites, fewer requests lower page load time.

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Base64 Encoding and Indian Language Scripts

Standard Base64 functions handle only ASCII characters. Encoding Hindi, Tamil, Bengali, or Gujarati text requires a UTF-8 wrapper that converts each character to its byte sequence first. Devanagari characters take 3 bytes each in UTF-8. That byte sequence then feeds into the Base64 algorithm.

Without the UTF-8 wrapper, encoding a Hindi string returns incorrect output or throws an error. ToolDekho's Base64 encoder runs the UTF-8 conversion automatically. Devanagari, Tamil, Telugu, Kannada, Malayalam, Bengali, Gujarati, and Punjabi scripts all encode and decode correctly.

How to Use the Base64 Encoder on ToolDekho

Open the tool and select Encode or Decode mode. The tool does not auto-detect direction.
Paste your input text or Base64 string into the input panel.
The output appears instantly in the browser. No text is sent to any server.
If decoding fails, check for whitespace or line breaks in the pasted string. Paste the Base64 value as a single unbroken line.

For binary files such as images, a dedicated file-to-Base64 converter is needed. The text tool accepts text input only.

Common Mistakes to Avoid

Mistake	Why It Fails	Fix
Pasting JWT segment without replacing `-` and `_`	Base64 URL alphabet differs from standard	Replace `-`→`+` and `_`→`/` first
Pasting with line breaks	`atob` rejects whitespace inside the string	Remove all line breaks before pasting
Using Base64 to protect secrets	Base64 is not encryption	Use AES or TLS for sensitive data
Encoding binary files as text	Text-mode encoding corrupts binary bytes	Use a file-to-Base64 tool instead

Understanding Padding Characters

Base64 works in groups of 3 bytes. When input length is not a multiple of 3, padding characters (=) complete the final group. One = means 1 byte of padding was added. Two == means 2 bytes were added. Output length is always a multiple of 4 characters.

Seeing == at the end of a Base64 string is completely normal. Many developers assume something went wrong when they spot it — nothing did. Removing those characters breaks decoders that expect strict padding.

Related reading: learn how developers handle URL encoding for query strings. You can also learn how to inspect HTTP headers in API testing.