先识别保护类型，
再选择恢复方式。
原创实测、可下载样本、明确适用边界。用可复核的证据回答 PDF、Excel 和 ZIP 密码问题。
OPEN PASSWORD / SHEET / STRUCTURE
SAME EXTENSION. DIFFERENT REVISIONS.
FORMAT / TOOL LIMIT / VALIDATION
文件后缀是线索，不是诊断结果。
先看文件究竟在哪一步阻止了您。
Workbook package parts unchanged in our worksheet-unprotect test.
See exactly what changed ↗实验室
实验文章目前提供英文完整版。
Excel password remover online: first identify what is actually locked
Five downloadable Excel test files show the difference between an opening password, worksheet protection and workbook structure protection. Includes a private, browser-only XLSX inspector.
阅读实验 ↗EXPERIMENT / 02 · Excel integrityHow to unprotect an Excel sheet: what changed in our integrity test?
A worksheet-unprotect test with formulas, formatting, a chart, merged cells and validation. See the two changed XML parts, twelve unchanged parts and the limits of the check.
阅读实验 ↗EXPERIMENT / 03 · PDF benchmarkPDF password recovery time: R3, R4, R5 and R6 tested on one RTX 4060
Known-password controls and short numeric-mask tests on generated PDF files. Compare measured candidate rates, the failed R2 control and a clearly labeled time estimator.
阅读实验 ↗EXPERIMENT / 04 · ZIP positive controlsLong ZIP password recovery: when a correct dictionary still reports no result
Five owned ZipCrypto samples with 31, 32, 51, 52 and 127-character known passwords expose a version-specific tool limit. Includes downloads, controls and a false-positive check.
阅读实验 ↗Show the work.
01 / RepeatablePublic fixtures, known test passwords and SHA-256 fingerprints.
02 / SpecificVersions, protection types and measured conditions accompany results.
03 / HonestFailed controls and untested cases stay visible. No invented success rates.