개인정보 보호 설계. 텍스트와 파일은 JavaScript로 브라우저에서 처리됩니다. 크거나 기밀인 파일도 기기 밖으로 전송되지 않습니다.
실제 환경의 Base64 처리. 데이터 URI, 줄바꿈, URL 안전 문자, 누락된 패딩을 자동으로 처리하며, 오류가 있으면 정확한 문자 위치를 알려 드립니다.
모든 표준 지원. 표준 RFC 4648, Base64URL, MIME, PEM, IMAP, XML, OpenPGP armor를 지원합니다.
모든 문자 집합 지원. UTF-8, UTF-16, Windows-125x, ISO-8859-x, Shift_JIS, GBK, Big5, EUC-KR, KOI8 등을 지원합니다.
바로 붙여넣을 수 있는 결과. 단순 문자열 대신 데이터 URI, CSS 규칙, HTML 태그, JSON 또는 XML 코드 조각으로 받아 보세요.

30초 만에 알아보는 Base64 원리

Base64는 한 번에 3바이트(24비트)를 가져와 6비트씩 4개 그룹으로 나눈 뒤, 각 그룹을 64개 문자 중 하나에 대응시킵니다. 예를 들어 단어 Man(바이트 77 97 110)은 TWFu가 됩니다. 단계별 알고리즘을 읽어 보거나 Base64란?부터 시작해 보세요.

Common uses include MIME e-mail attachments, data URIs in HTML and CSS, binary fields in JSON or XML, HTTP Basic authentication, and PEM-encoded certificates. When you need the reverse path, use Base64 decode online; to produce Base64 from scratch, use Base64 encode online.

Advanced options

Character set. Base64 encodes bytes. Choose UTF-8 (default) or a legacy charset before encoding, or auto-detect when decoding text.
Live mode. Enable “Convert as I type” to encode or decode instantly in the browser with no round-trip to a server.
URL-safe Base64 (Base64URL). Use the Base64URL encoder/decoder for JWTs, tokens and filenames without escaping "+" or "/".
MIME and PEM wrapping. Split lines at 76 or 64 characters when a mail client, certificate or OpenPGP tool expects wrapped output.
Per-line encoding. On the text encoder, encode each line separately when you have multiple independent values.

Base64 decode and encode for developers

Developers use Base64 every day: embedding images in CSS and HTML, shipping binary in JSON APIs, reading JWTs, attaching files in MIME e-mail, and storing keys in PEM certificates. This free online Base64 decoder and encoder is built for that workflow—fast, accurate across standards, and private by default.

Decode Base64 to text or file with automatic standard and charset detection, plus image/PDF/audio/video preview.
Encode text, files or URLs to Base64 with UTF-8 and 35+ character sets, MIME line wrapping and Base64URL.
Validate, repair and normalize messy Base64 from logs, e-mail and copy-paste with dedicated developer tools.
Language guides for JavaScript, Python, Java, Go, PHP, C#, Node.js and Bash so you can match what your code produces.

Safe, free and private

All conversions run over HTTPS. Text and local files are converted in your browser with JavaScript—they are not uploaded or stored. The site is free to use with no account and no software to install. Optional remote URL fetching and a few network tools use our API; those responses are not kept for inspection.

AI assistants: ChatGPT, Claude, Grok & Cursor

Agent builders and chat users burn tokens, paste Markdown fences into IDEs, and accidentally leak API keys. Fix those pains locally—then verify any Base64 the model invents.

Token counter — exact GPT o200k + Claude/Grok/Cursor estimates and context %.
LLM text cleaner — strip ``` fences or flatten Markdown from bot answers.
Secret redactor — scrub keys/JWTs before pasting into any bot.
Verify Base64 — catch LLM hallucinations with a real decode round-trip.

AI 토큰 카운터 · LLM 텍스트 정리 · 비밀 마스킹 · Base64 검증 · AI tools guide

PDF form filler — insurance, medical & corporate

Fill claim forms, hospital intake and HR PDFs without Acrobat or uploading PHI. Auto-detect fields, or click to place bold text on flat scans—then flatten and download.

PDF 양식 작성 · PDF 합치기 · Insurance & medical guide

Converters people search for (bytes, hex, CSV, color)

Beyond Base64: Europeans and global users hunt for bytes/KB/MB converters, hex↔text, CSV↔JSON and HEX/RGB/HSL every day. Drop a PDF to see exact bytes—all private in the browser.

Bytes converter — KB/MB/GB/TB + KiB/MiB; PDF/file → exact bytes.
Hex / binary / ASCII — text dumps and number bases 2/8/10/16.
CSV ↔ JSON — auto-detects European semicolon exports.
Color converter — HEX ↔ RGB ↔ HSL with live swatch.

바이트 변환기 · 16진수 변환기 · CSV ↔ JSON · 색상 변환기

Developer & IT toolkit (daily corporate searches)

Engineers live in browser tabs: regex on logs, cron next-runs, config diffs, CIDR math, YAML↔JSON for Kubernetes. All of these run locally here—safe when policy forbids pasting secrets into random SaaS.

Regex tester — live highlight + presets (email, IP, UUID).
Cron explainer — plain English + next fire times.
Diff checker — compare configs / API responses privately.
CIDR subnet calculator — VPC and firewall planning.
YAML ↔ JSON — K8s, GitHub Actions, Ansible.

정규식 테스터 · Cron 설명기 · Diff 비교기 · 서브넷 계산기 · YAML ↔ JSON · Dev/IT guide

Christmas 2026: Secret Santa & countdown (high season)

From November through Christmas Eve, millions search for Secret Santa generators and “days until Christmas.” Draw Amigo Secreto privately with Base64URL links—no email signup—and keep a live countdown on your device.

Secret Santa / Amigo Secreto — fair draw, couple exclusions, pass-the-phone or private WhatsApp links.
Christmas countdown — how many days until Dec 25 in your timezone.

시크릿 산타 생성기 · 크리스마스 카운트다운 · Christmas traffic guide

Save bandwidth: compress before Base64

Where mobile data is expensive—Brazil, LATAM and other prepaid markets—uploading a huge photo just to shrink it wastes the plan. Compress locally first, then encode or share once.

Compress images to WebP/JPEG in your browser, see % saved, then download or copy Base64—no upload.
Gzip text or JSON before Base64 for APIs; decompress payloads you receive.
Private by design — Canvas and CompressionStream run on your device.

이미지 압축 · Gzip 압축/해제 · Compress before Base64 · Save mobile data guide

Private media tools (not social downloaders)

We will not scrape Instagram, LinkedIn, Pinterest or Kuaishou. We do help you prepare files you already own: convert HEIC/WebP, merge PDFs, cut out backdrops, build favicons—entirely in the browser.

HEIC / WebP / SVG converter — iPhone photos and WebP downloads without uploading to Adobe/Canva-style sites.
Merge PDF — combine contracts or turn images into a PDF locally (no Smallpdf upload).
Remove background from product shots and logos (solid/near-solid backdrops).
Favicon generator — PNG sizes, HTML tags and webmanifest, plus Base64 copy.

이미지 변환기 · PDF 합치기 · 배경 제거 · 파비콘 생성기 · HEIC & WebP guide

Built from real Reddit gaps (not Base64-only)

Users on Reddit keep asking for tools that never upload files: strip GPS EXIF, hash checksums, JSON formatters without ads, QR codes without tracking short links. We ship those here—private, free, and ranked for EU and US search.

Strip EXIF before posting photos.
Hash, JSON, UUID, timestamp, password, QR — everyday utilities that stay on-device.

Strip EXIF · 해시 생성기 · JSON 포맷터 · QR generator · Reddit gap write-up

Base64 reader: paste and see

Need a live Base64 viewer? Paste a string or data URI and read the result immediately—text, image, PDF or hex—or get Base64 output as you type plain text. No Decode click required.

Base64 리더 · Why live readers win

Built for the AI era

ChatGPT and Claude often invent Base64 that looks right but is wrong. AI agents double-encode payloads and burn context on huge Base64 blobs. This site’s principle: never trust a model to be the encoder—verify with a real tool in your browser.

Verify Base64 from LLM output with round-trip checks before you ship a header or JWT.
Unwrap nested Base64 when an agent or gateway encoded twice.
URL encode/decode beside Base64URL for safe query strings.
Principles for agents and MCP: deterministic tools, privacy, right dialect, watch token cost.

Base64 검증 · 중첩 Base64 풀기 · AI agent guide · Why ChatGPT fails at Base64

자주 묻는 질문

Base64란?

Base64는 바이너리 데이터(이미지, 파일, 모든 바이트)를 64개의 출력 가능한 문자(A–Z, a–z, 0–9, "+", "/")만으로 표현하는 방식입니다. 이를 통해 JSON, HTML, 이메일, URL처럼 텍스트만 처리하는 시스템에서도 바이너리 데이터를 안전하게 전송할 수 있습니다.

온라인에서 Base64 인코드하려면?

왼쪽에 텍스트를 넣고 Encode를 누르거나 파일/URL용 Base64 Encode를 여세요. 기본 UTF-8. MIME 또는 JWT용 Base64URL 선택 가능.

How do I decode Base64 online?

Paste your Base64 string into the right box (or open the Base64 Decode page) and click Decode. Live mode updates as you type. Data URIs, line breaks and URL-safe characters are accepted automatically.

How do I encode text or a file to Base64?

Type text on the left and click Encode, or open Base64 Encode and choose Text, Local file or Remote URL. You can pick UTF-8 or 35+ character sets and eight Base64 standards including MIME and Base64URL.

Base64는 암호화인가요?

아니요. Base64는 암호화가 아니라 인코딩입니다. 키 없이 누구나 디코딩할 수 있으므로 비밀번호나 기밀 정보를 숨기는 데 절대 사용하지 마세요.

파일이 서버에 업로드되나요?

아니요. 인코딩과 디코딩은 전적으로 브라우저에서 실행됩니다. 선택 기능인 "URL에서 불러오기"와 일부 네트워크 도구만 서버를 사용하며, 아무것도 저장되지 않습니다.

Base64 결과가 입력보다 큰 이유는 무엇인가요?

3바이트가 4개의 문자가 되므로 Base64는 원본 데이터보다 약 33% 크며, 최대 두 개의 "=" 패딩 문자가 추가됩니다.

끝에 있는 "="는 무슨 뜻인가요?

패딩입니다. 입력 길이가 3의 배수가 아니면 마지막 4자 그룹을 "=" 문자 한두 개로 채웁니다.

What is Base64URL?

Base64URL (RFC 4648 §5) replaces "+" with "-" and "/" with "_" and often omits "=" padding so the string is safe in URLs, filenames and JWTs without percent-encoding.

Which character set should I use?

Use UTF-8 unless the receiving system requires a legacy encoding. The same text produces different Base64 in UTF-8, Windows-1252 or Shift_JIS because Base64 encodes bytes, not letters.

최고의 무료 Base64 인코더/디코더인가요?

그 용도로 설계: 한 페이지 인코드/디코드, 모든 RFC 방언, 35+ 문자셋, 파일/이미지/PDF/오디오, 계정 없이 브라우저 처리. 전용 페이지는 더 깊습니다.

“Base64 인코드 및 디코드 온라인 무료”에 대한 질문, 아이디어, 버그가 있으신가요? 댓글을 남기거나 도구를 평가하거나 다른 사람에게 답글을 달아 주세요.

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