Free online Base64 batch encoding and decoding tool with multi-line batch processing, URL Safe variant, and original text reference.
TL;DR: Free online Base64 batch processor with multi-line encode/decode, URL Safe variant, and original text reference. Greatly improves batch processing efficiency. Runs locally, no registration required.
For local tools, open DevTools → Network and search your input — it should not appear in requests.
Usage Guide
One image as base64, one text snippet encoded — fine for single items, but batch-processing dozens of files through copy-paste is painfully slow. This tool handles batch base64 encode/decode: multiple files and multiple lines in one pass, itemized output with bulk download, local execution.
1. How to use
- Upload multiple files or paste multiple lines of text (one record per line).
- Pick encode (text/file → base64) or decode direction (base64 → text).
- Output comes itemized; copy per-item or download all at once (.txt or per-file names).
2. Typical batch scenarios
- Generate image base64 for mock API responses — dozens of test images in one pass.
- Decode bulk base64 log fields — restore raw text from base64 fields extracted from JSON logs.
- Batch-encode small config files for transmission — half the operations of one-by-one.
- Watch file size: memory climbs with files over 10MB each — split into smaller batches.
3. Batch vs single boundaries
Batch tools earn their keep on repetitive work with identical shape and varying content: multiple images to base64 for frontend constants, multiple base64 strings back to readable logs. But batch processing amplifies one easily-missed issue — fault isolation. A single file failing to encode (corrupt, over limit) should be skipped and reported rather than failing the whole batch. Likewise, failed decode entries keep their raw input for individual debugging. This tool follows per-item independence: one failure never blocks the rest, and failed items are flagged.
FAQ
No. The entire batch encode/decode runs in your local browser — neither pasted text nor selected files ever reach a backend.
Two modes, batch encode and batch decode, with one item per line. Options include the URL Safe variant, keeping the original text for reference, and a custom separator. Beyond multi-line text, multiple files can also be handled in one pass, with per-item output and a bulk download.
Check the options first: the newline and URL-safe variant settings. Then the input itself: image data URLs still carrying their prefix, and invalid padding characters.
No — Base64 output running longer than the source is normal, not a failure. Before handing results downstream, spot-check one or two items to confirm they round-trip.
There is no theoretical line limit; speed depends on your device. Watch resource usage when decoding untrusted input, and validate your option combination on a minimal sample before running the full batch.
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