Endian Compare

Describe one packed structure as name:type, one field per line, and paste its bytes. Both byte orders update automatically after a brief typing pause; the initial sample is already decoded. Old output is cleared immediately while you edit. Blank input waits quietly; invalid input reports the problem without moving focus. Example restores the synthetic sample. Clear inputs empties both fields. Copy exports the headers and all decoded fields as tab-separated text (TSV).

Types: u8/i8, u16/i16, u32/i32, u64/i64, f16/f32/f64, char and pad. [N] repeats a type; # starts a structure comment. Names must be unique. Fields are contiguous: no automatic C-struct alignment, padding, offset or file-format detection. Use explicit pad[N] for known gaps. Arrays reverse byte order within each scalar, not the order of their elements.

Hex accepts contiguous pairs or tokens separated by whitespace, commas, semicolons, colons or underscores. Each token contains complete bytes and may start with 0x. Paste byte data only; remove any address and ASCII columns from hex dumps first. Integer values remain exact at 64 bits; IEEE half/single/double retain negative zero and show Infinity/NaN. Character bytes preserve their order and display nonprinting/non-ASCII bytes as backslash-x escapes, including NUL; pad fields show no interpreted value.

Offsets are hexadecimal addresses increasing from zero in both views. Big-endian corresponds to network byte order for multibyte numeric fields. The byte map contains the original buffer, including extra bytes beyond the structure. An incomplete structure is rejected; extra bytes are reported. Limits: 128 fields, 1,024 elements each, 16,384 structure characters, 64 KiB structure/buffer and 524,288 hex-input characters.

The shared browser store keeps only the exact structure and hex-input text on this device, including empty or invalid drafts. Larger drafts use bounded lossless packing. Decoded fields, TSV output, the generated byte map and scrolling are not saved. Draft bounds are 32,768 UTF-16 code units for the structure and 1,048,576 for hex text; processing limits above remain unchanged. A storage warning means changes may remain only in memory if persistent storage is full or blocked.

Long byte fields, character fields and arrays show a short preview with an ellipsis. Open the cell to inspect its complete value; copying always includes full values.