Encode text to Base64, decode Base64 back to text, or convert any file to a Base64 data URL. Everything runs 100% in your browser — nothing is uploaded.
Absolutely — Base64 remains essential in 2026 for embedding images in data URIs, encoding API tokens, email attachments (MIME), and JWT payloads. Every modern web developer still uses it weekly.
Is Base64 encoding secure or encrypted?
No — Base64 is encoding, not encryption. Anyone can decode it instantly, including with this free tool. In 2026, never use Base64 alone to hide passwords or secrets; always encrypt first, then encode if needed.
What is Base64?
Base64 is a way to represent binary data using only 64 safe text characters (A–Z, a–z, 0–9, +, /). Developers use it to embed images in HTML/CSS, encode API tokens, and pass binary data through text-only systems like JSON or email.
This tool also converts files to Base64 — pick any image or file and get a ready-to-use data URL. If the data URL is an image, you will see a live preview. The URL-safe variant swaps + and / for - and _ so the output works safely inside URLs and filenames.
Frequently Asked Questions
How do I encode text to Base64?
Type or paste your text in the input box, choose "Encode", and click Convert. The Base64 output appears instantly and you can copy it with one click.
How do I decode Base64 to text?
Paste the Base64 string, choose "Decode", and click Convert. If the string is invalid you will get a clear error message instead of broken output.
What is URL-safe Base64?
Standard Base64 uses + and / which have special meaning in URLs. URL-safe Base64 replaces them with - and _ so the encoded string can be used directly in links and filenames.
Is this Base64 tool free and private?
Yes. It is 100% free, no signup, and everything — including file conversion — happens locally in your browser. Your files are never uploaded anywhere.
Is Base64 the same as encryption?
No. Base64 is a reversible encoding with no key — anyone can decode it in a fraction of a second. It hides nothing; it only repackages binary data so it survives text-only systems like email and JSON. Never use it to protect passwords, API secrets, or personal information.
Why does Base64 output sometimes end with = signs?
The = is padding that keeps the output length a multiple of 4 characters when the input isn't a multiple of 3 bytes. A single = means the final group held 2 input bytes; == means it held just 1. Decoders strip the padding automatically, so you can ignore it.
When should I use URL-safe Base64?
Standard Base64 uses + and /, which have special meanings inside URLs and can get mangled by servers. URL-safe Base64 replaces them with - and _, so tokens, encoded parameters, and filenames survive links and query strings without extra escaping.
How Base64 encoding works, step by step
Base64 converts arbitrary binary data into 64 safe ASCII characters (A–Z, a–z, 0–9, +, /) so it can travel through text-only channels: email attachments, data URIs in HTML/CSS, JSON payloads, and HTTP authorization headers. It is an encoding, not encryption — it changes the representation, not the secrecy.
The method: take the input 3 bytes at a time (24 bits) and split them into four 6-bit groups; each group is a number from 0–63 that maps to one Base64 character. If the input length isn't a multiple of 3, the output is padded with = signs so its length stays a multiple of 4. Because 3 bytes become 4 characters, Base64 inflates data by about 33%.
Worked example — encoding "Man": the bytes are 4D 61 6E, i.e. bits 01001101 01100001 01101110. Regrouped into sixes: 010011 (19 → T), 010110 (22 → W), 000101 (5 → F), 101110 (46 → u) → "TWFu". Encoding "Ma" (only 2 bytes) gives "TWE=" — the single = is the padding for the missing third byte.
Practical tips: use the URL-safe variant (which swaps + → − and / → _) whenever encoded data goes into URLs or filenames, since + and / have special meanings there. Limitation: anyone can decode Base64 instantly — never use it to "protect" passwords, tokens, or personal data; and don't Base64-encode huge files, since the 33% overhead adds up fast.
Where you'll meet Base64 in the wild: every JWT (JSON Web Token) is three Base64URL-encoded segments joined by dots — header.payload.signature — with padding stripped, which is why JWTs never end in "=". Data URIs embed images directly in HTML/CSS as data:image/png;base64,iVBORw0KG…, eliminating HTTP requests for tiny icons (worth it under ~2–4 KB; above that, separate files compress and cache better). Email attachments use MIME Base64 with line breaks every 76 characters — a formatting rule, not a different encoding. One more subtlety: Base64 operates on bytes, so encoding text first requires choosing a character encoding — UTF-8 is the standard, and encoding the same string as UTF-16 produces completely different output. When debugging, always confirm which byte encoding the other side expects.