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Generate random files of any size and format on demand, including text and binary data formats.
Range: 1-1024 KB. Out-of-range values are auto-corrected
Set parameters to generate and download a random file
Overview
Understand what the tool solves, how it works, and the boundaries of its data.
Choose a filename, a size in kilobytes, and one of four output formats: printable text, hexadecimal text, Base64 text, or raw binary. The size field is clamped to 1–1,024 KB, but reliable generation is limited to 1–64 KB: the browser random-byte request is made in one call, and the Web Cryptography specification limits each such call to 65,536 bytes. Values above that may fail even though the field accepts them.
The size setting describes the random bytes before text encoding. Binary keeps those bytes as-is. Printable text maps each byte to one visible ASCII character, so its content length remains one character per input byte. Hex writes two characters for every byte, doubling the text length. Base64 represents each group of three bytes with four characters, with padding when needed. For 1 KB (1,024 bytes), expect 1,024 printable characters, 2,048 hex characters, or 1,368 Base64 characters. Text encodings can therefore produce a larger downloaded file than the selected source size.
Each generation creates a fresh sample; there is no seed field for recreating a previous sequence. The preview shows at most the first 2,000 text characters. For binary output it reports the byte count rather than displaying arbitrary bytes. Download saves the complete current payload.
Guide
Follow the workflow and verify inputs and outputs with practical examples.
Enter a base name. The selected format supplies a .txt or .bin extension when the name does not already include a dot. Avoid relying on an extension alone to indicate how the contents are encoded.
Use a whole-number value from 1 to 64 KB for reliable generation. Although the input accepts larger values, one request above 65,536 bytes exceeds the browser API limit and may fail.
Choose text for visible printable characters, HEX or Base64 when the test expects encoded text, or binary when it needs raw bytes. Confirm the receiving program expects that representation.
Regenerate to create a new sample. The preview is partial for text and only a byte-count label for binary. Download the full currently generated content when ready.
Use cases
See how the tool fits into real work and everyday tasks.
Use printable text, HEX, or Base64 to check how an application accepts and displays text files. Record both the selected source-byte size and encoded output length when comparing parser limits.
Generate a small binary sample to test a file picker, transfer path, or reader that expects arbitrary bytes. Regenerate for a new sample; this page does not provide a repeatable seed.
Compare the same input size across formats to see why hexadecimal and Base64 text expand beyond the underlying bytes. Use the displayed preview as a sample, not as the complete file when it is longer than the preview limit.
Q&A
Find concise answers to common questions and confusing cases.
The field allows values up to 1,024 KB, but generation makes one random-byte request. The browser specification caps that request at 65,536 bytes, so use 64 KB or less for a dependable result.
Each byte is written as two hexadecimal characters. The size control measures the bytes before encoding, so a 1 KB sample becomes 2,048 text characters in HEX.
No. It requests a new random sample; there is no seed or saved-sequence control. Download the current result before regenerating if you need to keep that sample.
No. Text previews are capped at 2,000 characters. Binary preview displays the byte count, while the download contains the full generated data.
Notes
Review scope, result limitations, and important precautions before use.
This tool is intended for test files and demonstrations. Do not use generated output as a password, encryption key, authentication token, or other security credential. The specification directs key creation to dedicated key-generation methods rather than the general random-value method.
Stay within 64 KB to avoid the single-call size limit. A size shown in the input is not proof that a larger request completed successfully; confirm the preview and download behavior before using a sample in a test workflow.
Related
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