Benchmark: Bytes to BigInt64

HTML Preparation code:

<!--your preparation HTML code goes here-->

Script Preparation code:

function bytesToBigIntLoop(bytes) {
    let value = 0n;
    let bits = 8n;
    for (let i = 0; i < bytes.length; i++) {
        value = (value << bits) + BigInt(bytes[i]);
    }
    return value;
}

function bytesToBigIntDataView(bytes) {
    const view = new DataView(bytes.buffer);
    return view.getBigInt64(0);
}

function bytesToBigIntHex(bytes) {
    return BigInt('0x' + bytes.map(byte => byte.toString(16).padStart(2, '0')).join(''))
}

function bytesToBigIntLoop2(data) {
    let encoded = 0n;

    for (let i = 0, l = data.length; i < l; i++) {

        encoded |= BigInt(data[i]) << BigInt((l - i - 1) * 8);

    }

    return encoded;

}

function bytesToBigIntSplit(data) {
    let high = 0;
    high = (high << 8) | data[0];
    high = (high << 8) | data[1];
    high = (high << 8) | data[2];
    high = (high << 8) | data[3];

    let low = 0;
    low = (low << 8) | data[4];
    low = (low << 8) | data[5];
    low = (low << 8) | data[6];
    low = (low << 8) | data[7];

    return (BigInt(low) << 32n) | BigInt(high);
}

Tests:

Loop
bytesToBigIntLoop(new Uint8Array([255,255,255,0,0,0,0,0]))
DataView
bytesToBigIntDataView(new Uint8Array([255,255,255,0,0,0,0,0]))
Hex
bytesToBigIntHex(new Uint8Array([255,255,255,0,0,0,0,0]))
Loop2
bytesToBigIntLoop2(new Uint8Array([255,255,255,0,0,0,0,0]))
Split
bytesToBigIntSplit(new Uint8Array([255,255,255,0,0,0,0,0]))

Historical Performance Data aggregated from 7 community runs

Desktop Results:

Firefox 7 runs

Loop

1.9M/s

Hex

1.4M/s

DataView

1.3M/s

Fastest: Loop (1.4x faster)

View exact numbers

✓ Loop: 1,865,493 ops/sec
• Hex: 1,406,419 ops/sec
• DataView: 1,314,712 ops/sec

Results show median performance across all community submissions. Run this benchmark yourself to verify on your device.

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Loop
DataView
Hex
Loop2
Split

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: one year ago)

User agent: Mozilla/5.0 (Linux; Android 10; K) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/126.0.0.0 Mobile Safari/537.36

Browser/OS: Chrome Mobile 126 on Android

View result in a separate tab

Split

9.5M/s

Loop

3.3M/s

Loop2

2.3M/s

DataView

1.4M/s

Hex

923K/s

View exact numbers

Test name	Executions per second
✓ Split	9,455,548 Ops/sec
Loop	3,259,181 Ops/sec
Loop2	2,321,812 Ops/sec
DataView	1,374,523 Ops/sec
Hex	923,228 Ops/sec

Bytes to BigInt64 (version: 7)

Comparing performance of: `Loop vs DataView vs Hex vs Loop2 vs Split`

Created: one year ago by: Registered User

Go to the latest result

Loop

DataView

Hex

Loop2

Split

Historical Performance Data aggregated from 7 community runs

Desktop Results:

Firefox 7 runs

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

Bytes to BigInt64 (version: 7)

Comparing performance of: Loop vs DataView vs Hex vs Loop2 vs Split

Created: one year ago by: Registered User

Go to the latest result

Loop

DataView

Hex

Loop2

Split

Historical Performance Data aggregated from 7 community runs

Desktop Results:

Firefox 7 runs

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

Related benchmarks

Comparing performance of: `Loop vs DataView vs Hex vs Loop2 vs Split`