使用结果前如何检查？
哈希匹配用于核对所选算法下的字节一致性，不证明文件发布者身份。应通过可信渠道取得预期值；完整性校验优先使用 SHA-256 或更强算法。
File Checksum Calculator可以处理什么？
File Checksum Calculator 用于在浏览器中检查数据，并清楚显示处理结果和限制。 已核对的功能： Local file hashing, Expected-value verification, Four algorithms, 200 MB guardrail.
A matching checksum proves equality, not trust
A match shows that the file bytes equal the bytes used to publish the checksum. It does not prove who published either value; use a signed release, authenticated channel, or package signature when origin matters.
如何使用？
- Choose SHA-256, SHA-512, SHA-1, or MD5, then select one local file no larger than 200 MB.
- Optionally paste the publisher’s expected checksum; spaces and letter case are ignored during comparison.
- Confirm Match or Mismatch and copy the calculated checksum with its algorithm name.
实际输入输出示例
Verify a three-byte text file
输入
File bytes: 61 62 63 (UTF-8 text "abc")
Algorithm: SHA-256输出
ba7816bf8f01cfea414140de5dae2223b00361a396177a9cb410ff61f20015adThis known SHA-256 value verifies that the selected file contains exactly the three bytes for abc.
常见错误与修复方法
| 现象 | 可能原因 | 修复方法 |
|---|---|---|
| The calculated value does not match the published checksum. | The download is different, damaged, transformed, or compared with the wrong algorithm. | Confirm the algorithm and source, download the file again, and do not use it until the mismatch is explained. |
| The file is rejected before hashing. | The selected file exceeds the page’s 200 MB browser-memory guardrail. | Use a streaming desktop checksum utility for larger files. |
Important behavior of File Checksum
该工具的实际边界： A matching checksum proves byte equality, not that the publisher or file is trustworthy.
标准与实现参考
- W3C Web Cryptography API (opens in a new tab)Defines the browser digest API used for SHA calculations.
- NIST FIPS 180-4 — Secure Hash Standard (opens in a new tab)Specifies the SHA algorithms exposed by this tool.
关于File Checksum的常见问题
Does the File Checksum upload my input?
No. Processing runs in the current browser tab, and the page does not send tool input to a KitLumi processing endpoint.
What input does the File Checksum accept?
It accepts one local file up to 200 MB and an optional expected checksum. The workspace checks the input and reports malformed or unsupported values before it produces a result.
What does the File Checksum produce?
It produces an MD5, SHA-1, SHA-256, or SHA-512 hexadecimal digest. Copy and download controls appear when the output format supports them.
What limitation should I know?
A matching checksum proves byte equality, not that the publisher or file is trustworthy.
更新记录
本次实质更新： File Checksum: Added Local file hashing, Expected-value verification, Four algorithms, 200 MB guardrail, responsive controls, explicit runtime disclosure, and task-specific examples and limitations. 2026-10-15：补充结果检查步骤和具体能力边界。