Encode text to Base64, decode Base64 back to readable text, and handle common issues like Base64URL input, missing padding, and malformed strings. This free online Base64 encoder and decoder works directly in your browser and is especially useful when you need to decode JWT-style Base64URL data, validate Base64 input during decoding, or fix Base64 padding problems without installing anything.
Convert plain text, JSON, or any UTF-8 data into Base64 encoding.
Decode Base64 strings back to readable text instantly.
Base64URL / JWT
Decode URL-safe Base64 tokens (JWTs, API keys, OAuth)
Use - and _ instead of + and / for web URLs
Remove trailing = signs from output
Keep whitespace for better readability
Check whether pasted Base64 is valid before decoding
Need to convert a JPG, PNG, SVG, WebP, or other image file? Use our Image to Base64 Converter.
This tool is best for text-based Base64 encoding and decoding. For image files, use the dedicated Image to Base64 Converter.
Base64 is a text-based encoding format used to represent binary or structured data with a limited set of ASCII characters. It is widely used in web development, APIs, JSON payloads, email systems, tokens, and data transfer workflows. Many people use a Base64 encoder and decoder simply to convert text, but real-world Base64 often also involves URL-safe variants, missing padding, or malformed input that needs extra care during decoding.
Paste your input, choose whether you want to encode or decode, and the tool converts it instantly in your browser. You can use it as a standard Base64 encoder, a Base64 decoder, or for practical troubleshooting when a string does not decode cleanly. This page is especially helpful for Base64URL decode workflows, pasted data from APIs, and strings that need padding repaired before decoding.
Standard Base64 uses letters, numbers, plus (+), slash (/), and optional equals signs (=) for padding. Small formatting differences can make a big difference during decoding. Some systems use URL-safe Base64, which replaces plus and slash with hyphen (-) and underscore (_). Other strings may fail because of invalid characters, broken formatting, or missing padding, which is why a good Base64 decoder should help users handle these cases clearly.
A browser-based Base64 tool is useful when you need quick results during development, testing, debugging, or day-to-day work. You can encode text to Base64, decode Base64 back to text, inspect suspicious values, and troubleshoot malformed strings without writing extra code. It is especially convenient when you need a fast answer for JWT-style payloads, copied API data, or Base64 values pasted from another system.
This tool is designed not only for ordinary Base64 decoding, but also for common troubleshooting tasks. It can help when you want to validate Base64 during decoding, understand why a string fails, or deal with malformed input caused by bad characters, incorrect formatting, or incomplete data. It is also useful for Base64 padding issues, because many pasted values fail only because they are missing the expected equals signs at the end.
Some systems use Base64URL instead of standard Base64. In that variant, plus (+) becomes hyphen (-), slash (/) becomes underscore (_), and padding may be omitted. That is common in JWT tokens, OAuth-related data, and URL-safe payloads passed between web services. If you need to decode a JWT-style segment or another URL-safe Base64 string, this page helps you handle Base64URL input more reliably.
A valid Base64 string usually follows strict alphabet and length rules. In practice, however, people often paste strings with whitespace, missing padding, URL-safe characters, or a data URL prefix such as data:image/png;base64,. That is why this tool is useful for more than simple conversion. It supports practical troubleshooting around Base64 padding, validation during decode, and common formatting mistakes, making it easier to work with real-world Base64 data.
Paste your content into the input box, then choose whether you want to encode or decode. If you want to convert readable text into Base64, use encode. If you already have a Base64 string and want to turn it back into readable text, use decode. For URL-safe or JWT-style strings, use the Base64URL or JWT-friendly option so the tool can handle the different characters and padding behavior correctly.
Yes. This Base64 encoder and decoder is free to use in your browser. You can paste text, encode it to Base64, decode Base64 strings, and troubleshoot common issues like Base64 padding or malformed input without creating an account.
No. Base64 is an encoding format, not encryption. It changes data into a text-safe representation, but it does not protect secrets by itself. Anyone who has the Base64 string can usually decode it easily. If you need confidentiality, you need real encryption rather than Base64 alone.
Base64 is often used when systems need to move binary or structured data through channels that are mainly text-based. That includes APIs, JSON payloads, email content, tokens, and embedded data. It makes data easier to transport safely, although it also increases size somewhat. Many developers therefore need a quick Base64 decoder or Base64 encoder while testing or debugging these workflows.
Yes. This Base64 tool supports UTF-8 text, including Unicode characters, accented letters, and emoji. That matters when you are encoding or decoding real text from modern websites, apps, and APIs rather than only plain ASCII content.
URL-safe Base64, often called Base64URL, is a variant of Base64 that replaces plus (+) with hyphen (-) and slash (/) with underscore (_). It may also omit the trailing equals signs used for padding. This format is common in JWT segments, signed URLs, and web-related tokens. If you need Base64URL decode behavior, use the URL-safe or JWT-friendly option on this page.
You can decode or inspect Base64 text that represents image data, especially when it appears inside a data URL such as data:image/png;base64,... However, this page is mainly designed for text-focused Base64 encoding, decoding, and troubleshooting rather than full file reconstruction or binary download workflows.
This tool is designed to follow standard Base64 rules while also helping with practical real-world inputs. That includes handling common formatting issues such as whitespace, URL-safe characters, and missing padding in the right context. The goal is to provide accurate Base64 encode and decode results while also helping users understand why some malformed strings fail.
A common example is that Hello World encoded in Base64 becomes SGVsbG8gV29ybGQ=. Simple examples like this are useful for checking whether a Base64 encoder or decoder is working as expected before you move on to larger or more technical inputs.
Base64 padding uses one or two equals signs (=) at the end of a string so the encoded output fits the expected length rules. Some systems omit padding, especially in Base64URL contexts, which can cause decoding problems if the input is not normalized first. That is why Base64 padding matters: many strings fail not because the data is wrong, but because the formatting is incomplete.
Use this Base64 Encoder & Decoder to convert text to Base64, decode Base64 back to readable text, and troubleshoot URL-safe input, padding issues, or malformed strings. Fast, simple, and free.
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