diff --git a/internal/internal.go b/internal/internal.go
index c6e1391c5..d595d1e18 100644
--- a/internal/internal.go
+++ b/internal/internal.go
@@ -7,17 +7,18 @@ import (
 	"errors"
 	"fmt"
 	"io"
-	"math"
+	"math/big"
 	"math/rand"
 	"os"
 	"os/exec"
 	"runtime"
-	"strconv"
 	"strings"
 	"sync"
 	"syscall"
 	"time"
 	"unicode"
+
+	"github.com/influxdata/telegraf/internal/choice"
 )
 
 const alphanum string = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz"
@@ -257,145 +258,147 @@ func CompressWithGzip(data io.Reader) (io.ReadCloser, error) {
 // The location is a location string suitable for time.LoadLocation.  Unix
 // times do not use the location string, a unix time is always return in the
 // UTC location.
-func ParseTimestamp(format string, timestamp interface{}, location string) (time.Time, error) {
+func ParseTimestamp(format string, timestamp interface{}, location string, separator ...string) (time.Time, error) {
 	switch format {
 	case "unix", "unix_ms", "unix_us", "unix_ns":
-		return parseUnix(format, timestamp)
-	default:
-		if location == "" {
-			location = "UTC"
+		sep := []string{",", "."}
+		if len(separator) > 0 {
+			sep = separator
 		}
-		return parseTime(format, timestamp, location)
+		return parseUnix(format, timestamp, sep)
+	default:
+		v, ok := timestamp.(string)
+		if !ok {
+			return time.Unix(0, 0), errors.New("unsupported type")
+		}
+		return parseTime(format, v, location)
 	}
 }
 
-func parseUnix(format string, timestamp interface{}) (time.Time, error) {
-	integer, fractional, err := parseComponents(timestamp)
+// parseTime parses a timestamp in unix format with different resolutions
+func parseUnix(format string, timestamp interface{}, separator []string) (time.Time, error) {
+	// Extract the scaling factor to nanoseconds from "format"
+	var factor int64
+	switch format {
+	case "unix":
+		factor = int64(time.Second)
+	case "unix_ms":
+		factor = int64(time.Millisecond)
+	case "unix_us":
+		factor = int64(time.Microsecond)
+	case "unix_ns":
+		factor = int64(time.Nanosecond)
+	}
+
+	zero := time.Unix(0, 0)
+
+	// Convert the representation to time
+	switch v := timestamp.(type) {
+	case int, int8, int16, int32, int64, uint, uint8, uint16, uint32, uint64:
+		t, err := ToInt64(v)
+		if err != nil {
+			return zero, err
+		}
+		return time.Unix(0, t*factor).UTC(), nil
+	case float32, float64:
+		ts, err := ToFloat64(v)
+		if err != nil {
+			return zero, err
+		}
+
+		// Parse the float as a precise fraction to avoid precision loss
+		f := big.Rat{}
+		if f.SetFloat64(ts) == nil {
+			return zero, errors.New("invalid number")
+		}
+		return timeFromFraction(&f, factor), nil
+	case string:
+		// Sanitize the string to have no thousand separators and dot
+		// as decimal separator to ease later parsing
+		v = sanitizeTimestamp(v, separator)
+
+		// Parse the string as a precise fraction to avoid precision loss
+		f := big.Rat{}
+		if _, ok := f.SetString(v); !ok {
+			return zero, errors.New("invalid number")
+		}
+		return timeFromFraction(&f, factor), nil
+	}
+
+	return zero, errors.New("unsupported type")
+}
+
+func timeFromFraction(f *big.Rat, factor int64) time.Time {
+	// Extract the numerator and denominator and scale to nanoseconds
+	num := f.Num()
+	denom := f.Denom()
+	num.Mul(num, big.NewInt(factor))
+
+	// Get the integer (non-fractional part) of the timestamp and convert
+	// it into time
+	t := big.Int{}
+	t.Div(num, denom)
+
+	return time.Unix(0, t.Int64()).UTC()
+}
+
+// sanitizeTimestamp removes thousand separators and uses dot as
+// decimal separator. Returns also a boolean indicating success.
+func sanitizeTimestamp(timestamp string, decimalSeparartor []string) string {
+	// Remove thousand-separators that are not used for decimal separation
+	sanitized := timestamp
+	for _, s := range []string{" ", ",", "."} {
+		if !choice.Contains(s, decimalSeparartor) {
+			sanitized = strings.ReplaceAll(sanitized, s, "")
+		}
+	}
+
+	// Replace decimal separators by dot to have a standard, parsable format
+	for _, s := range decimalSeparartor {
+		// Make sure we replace only the first occurrence of any separator.
+		if strings.Contains(sanitized, s) {
+			return strings.Replace(sanitized, s, ".", 1)
+		}
+	}
+	return sanitized
+}
+
+// parseTime parses a string timestamp according to the format string.
+func parseTime(format string, timestamp string, location string) (time.Time, error) {
+	loc, err := time.LoadLocation(location)
 	if err != nil {
 		return time.Unix(0, 0), err
 	}
 
 	switch strings.ToLower(format) {
-	case "unix":
-		return time.Unix(integer, fractional).UTC(), nil
-	case "unix_ms":
-		return time.Unix(0, integer*1e6).UTC(), nil
-	case "unix_us":
-		return time.Unix(0, integer*1e3).UTC(), nil
-	case "unix_ns":
-		return time.Unix(0, integer).UTC(), nil
-	default:
-		return time.Unix(0, 0), errors.New("unsupported type")
-	}
-}
-
-// Returns the integers before and after an optional decimal point.  Both '.'
-// and ',' are supported for the decimal point.  The timestamp can be an int64,
-// float64, or string.
-//
-//	ex: "42.5" -> (42, 5, nil)
-func parseComponents(timestamp interface{}) (int64, int64, error) {
-	switch ts := timestamp.(type) {
-	case string:
-		parts := strings.SplitN(ts, ".", 2)
-		if len(parts) == 2 {
-			return parseUnixTimeComponents(parts[0], parts[1])
-		}
-
-		parts = strings.SplitN(ts, ",", 2)
-		if len(parts) == 2 {
-			return parseUnixTimeComponents(parts[0], parts[1])
-		}
-
-		integer, err := strconv.ParseInt(ts, 10, 64)
-		if err != nil {
-			return 0, 0, err
-		}
-		return integer, 0, nil
-	case int8:
-		return int64(ts), 0, nil
-	case int16:
-		return int64(ts), 0, nil
-	case int32:
-		return int64(ts), 0, nil
-	case int64:
-		return ts, 0, nil
-	case uint8:
-		return int64(ts), 0, nil
-	case uint16:
-		return int64(ts), 0, nil
-	case uint32:
-		return int64(ts), 0, nil
-	case uint64:
-		return int64(ts), 0, nil
-	case float32:
-		integer, fractional := math.Modf(float64(ts))
-		return int64(integer), int64(fractional * 1e9), nil
-	case float64:
-		integer, fractional := math.Modf(ts)
-		return int64(integer), int64(fractional * 1e9), nil
-	default:
-		return 0, 0, errors.New("unsupported type")
-	}
-}
-
-func parseUnixTimeComponents(first, second string) (int64, int64, error) {
-	integer, err := strconv.ParseInt(first, 10, 64)
-	if err != nil {
-		return 0, 0, err
-	}
-
-	// Convert to nanoseconds, dropping any greater precision.
-	buf := []byte("000000000")
-	copy(buf, second)
-
-	fractional, err := strconv.ParseInt(string(buf), 10, 64)
-	if err != nil {
-		return 0, 0, err
-	}
-	return integer, fractional, nil
-}
-
-// ParseTime parses a string timestamp according to the format string.
-func parseTime(format string, timestamp interface{}, location string) (time.Time, error) {
-	switch ts := timestamp.(type) {
-	case string:
-		loc, err := time.LoadLocation(location)
-		if err != nil {
-			return time.Unix(0, 0), err
-		}
-		switch strings.ToLower(format) {
-		case "ansic":
-			format = time.ANSIC
-		case "unixdate":
-			format = time.UnixDate
-		case "rubydate":
-			format = time.RubyDate
-		case "rfc822":
-			format = time.RFC822
-		case "rfc822z":
-			format = time.RFC822Z
-		case "rfc850":
-			format = time.RFC850
-		case "rfc1123":
-			format = time.RFC1123
-		case "rfc1123z":
-			format = time.RFC1123Z
-		case "rfc3339":
-			format = time.RFC3339
-		case "rfc3339nano":
-			format = time.RFC3339Nano
-		case "stamp":
-			format = time.Stamp
-		case "stampmilli":
-			format = time.StampMilli
-		case "stampmicro":
-			format = time.StampMicro
-		case "stampnano":
-			format = time.StampNano
-		}
-		return time.ParseInLocation(format, ts, loc)
-	default:
-		return time.Unix(0, 0), errors.New("unsupported type")
+	case "ansic":
+		format = time.ANSIC
+	case "unixdate":
+		format = time.UnixDate
+	case "rubydate":
+		format = time.RubyDate
+	case "rfc822":
+		format = time.RFC822
+	case "rfc822z":
+		format = time.RFC822Z
+	case "rfc850":
+		format = time.RFC850
+	case "rfc1123":
+		format = time.RFC1123
+	case "rfc1123z":
+		format = time.RFC1123Z
+	case "rfc3339":
+		format = time.RFC3339
+	case "rfc3339nano":
+		format = time.RFC3339Nano
+	case "stamp":
+		format = time.Stamp
+	case "stampmilli":
+		format = time.StampMilli
+	case "stampmicro":
+		format = time.StampMicro
+	case "stampnano":
+		format = time.StampNano
 	}
+	return time.ParseInLocation(format, timestamp, loc)
 }
diff --git a/internal/internal_test.go b/internal/internal_test.go
index 5c02e4098..22f5a3bad 100644
--- a/internal/internal_test.go
+++ b/internal/internal_test.go
@@ -394,8 +394,8 @@ func TestParseTimestamp(t *testing.T) {
 		format    string
 		timestamp interface{}
 		location  string
+		separator []string
 		expected  time.Time
-		err       bool
 	}{
 		{
 			name:      "parse layout string in utc",
@@ -404,13 +404,6 @@ func TestParseTimestamp(t *testing.T) {
 			location:  "UTC",
 			expected:  rfc3339("2019-02-20T21:50:34Z"),
 		},
-		{
-			name:      "parse layout string with invalid timezone",
-			format:    "2006-01-02 15:04:05",
-			timestamp: "2019-02-20 21:50:34",
-			location:  "InvalidTimeZone",
-			err:       true,
-		},
 		{
 			name:      "layout regression 6386",
 			format:    "02.01.2006 15:04:05",
@@ -447,6 +440,48 @@ func TestParseTimestamp(t *testing.T) {
 			timestamp: "1568338208.00000050042",
 			expected:  rfc3339("2019-09-13T01:30:08.000000500Z"),
 		},
+		{
+			name:      "unix seconds with thousand separator only (dot)",
+			format:    "unix",
+			timestamp: "1.568.338.208",
+			separator: []string{","},
+			expected:  rfc3339("2019-09-13T01:30:08Z"),
+		},
+		{
+			name:      "unix seconds with thousand separator only (comma)",
+			format:    "unix",
+			timestamp: "1,568,338,208",
+			separator: []string{"."},
+			expected:  rfc3339("2019-09-13T01:30:08Z"),
+		},
+		{
+			name:      "unix seconds with thousand separator only (space)",
+			format:    "unix",
+			timestamp: "1 568 338 208",
+			separator: []string{"."},
+			expected:  rfc3339("2019-09-13T01:30:08Z"),
+		},
+		{
+			name:      "unix seconds with thousand separator only (underscore)",
+			format:    "unix",
+			timestamp: "1_568_338_208",
+			separator: []string{"."},
+			expected:  rfc3339("2019-09-13T01:30:08Z"),
+		},
+		{
+			name:      "unix seconds with thousand and decimal separator (US)",
+			format:    "unix",
+			timestamp: "1,568,338,208.500",
+			separator: []string{"."},
+			expected:  rfc3339("2019-09-13T01:30:08.500Z"),
+		},
+		{
+			name:      "unix seconds with thousand and decimal separator (EU)",
+			format:    "unix",
+			timestamp: "1.568.338.208,500",
+			separator: []string{","},
+			expected:  rfc3339("2019-09-13T01:30:08.500Z"),
+		},
 		{
 			name:      "unix seconds integer",
 			format:    "unix",
@@ -459,6 +494,12 @@ func TestParseTimestamp(t *testing.T) {
 			timestamp: float64(1568338208.500),
 			expected:  rfc3339("2019-09-13T01:30:08.500Z"),
 		},
+		{
+			name:      "unix seconds float exponential",
+			format:    "unix",
+			timestamp: float64(1.5683382085e+9),
+			expected:  rfc3339("2019-09-13T01:30:08.500Z"),
+		},
 		{
 			name:      "unix milliseconds",
 			format:    "unix_ms",
@@ -466,10 +507,10 @@ func TestParseTimestamp(t *testing.T) {
 			expected:  rfc3339("2019-09-13T01:30:08.500Z"),
 		},
 		{
-			name:      "unix milliseconds with fractional is ignored",
+			name:      "unix milliseconds with fractional",
 			format:    "unix_ms",
 			timestamp: "1568338208500.42",
-			expected:  rfc3339("2019-09-13T01:30:08.500Z"),
+			expected:  rfc3339("2019-09-13T01:30:08.50042Z"),
 		},
 		{
 			name:      "unix microseconds",
@@ -483,6 +524,12 @@ func TestParseTimestamp(t *testing.T) {
 			timestamp: "1568338208000000500",
 			expected:  rfc3339("2019-09-13T01:30:08.000000500Z"),
 		},
+		{
+			name:      "unix nanoseconds exponential",
+			format:    "unix_ns",
+			timestamp: "1.5683382080000005e+18",
+			expected:  rfc3339("2019-09-13T01:30:08.000000500Z"),
+		},
 		{
 			name:      "rfc339 test",
 			format:    "RFC3339",
@@ -591,13 +638,75 @@ func TestParseTimestamp(t *testing.T) {
 	}
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {
-			tm, err := ParseTimestamp(tt.format, tt.timestamp, tt.location)
-			if tt.err {
-				require.Error(t, err)
-			} else {
-				require.NoError(t, err)
-				require.Equal(t, tt.expected, tm)
-			}
+			tm, err := ParseTimestamp(tt.format, tt.timestamp, tt.location, tt.separator...)
+			require.NoError(t, err)
+			require.Equal(t, tt.expected, tm)
+		})
+	}
+}
+
+func TestParseTimestampInvalid(t *testing.T) {
+	tests := []struct {
+		name      string
+		format    string
+		timestamp interface{}
+		location  string
+		expected  string
+	}{
+		{
+			name:      "too few digits",
+			format:    "2006-01-02 15:04:05",
+			timestamp: "2019-02-20 21:50",
+			expected:  "cannot parse \"\" as \":\"",
+		},
+		{
+			name:      "invalid timezone",
+			format:    "2006-01-02 15:04:05",
+			timestamp: "2019-02-20 21:50:34",
+			location:  "InvalidTimeZone",
+			expected:  "unknown time zone InvalidTimeZone",
+		},
+		{
+			name:      "invalid layout",
+			format:    "rfc3399",
+			timestamp: "09.07.2019 00:11:00",
+			expected:  "cannot parse \"09.07.2019 00:11:00\" as \"rfc\"",
+		},
+		{
+			name:      "layout not matching time",
+			format:    "rfc3339",
+			timestamp: "09.07.2019 00:11:00",
+			expected:  "cannot parse \"7.2019 00:11:00\" as \"2006\"",
+		},
+		{
+			name:      "unix wrong type",
+			format:    "unix",
+			timestamp: true,
+			expected:  "unsupported type",
+		},
+		{
+			name:      "unix multiple separators (dot)",
+			format:    "unix",
+			timestamp: "1568338.208.500",
+			expected:  "invalid number",
+		},
+		{
+			name:      "unix multiple separators (comma)",
+			format:    "unix",
+			timestamp: "1568338,208,500",
+			expected:  "invalid number",
+		},
+		{
+			name:      "unix multiple separators (mixed)",
+			format:    "unix",
+			timestamp: "1,568,338,208.500",
+			expected:  "invalid number",
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			_, err := ParseTimestamp(tt.format, tt.timestamp, tt.location)
+			require.ErrorContains(t, err, tt.expected)
 		})
 	}
 }
diff --git a/plugins/parsers/xpath/parser.go b/plugins/parsers/xpath/parser.go
index 7d3e5e930..3fd3bdf15 100644
--- a/plugins/parsers/xpath/parser.go
+++ b/plugins/parsers/xpath/parser.go
@@ -119,6 +119,17 @@ func (p *Parser) Init() error {
 		return errors.New("missing default metric name")
 	}
 
+	// Update the configs with default values
+	for i, config := range p.Configs {
+		if config.Selection == "" {
+			config.Selection = "/"
+		}
+		if config.TimestampFmt == "" {
+			config.TimestampFmt = "unix"
+		}
+		p.Configs[i] = config
+	}
+
 	return nil
 }
 
@@ -138,9 +149,6 @@ func (p *Parser) Parse(buf []byte) ([]telegraf.Metric, error) {
 	metrics := make([]telegraf.Metric, 0)
 	p.Log.Debugf("Number of configs: %d", len(p.Configs))
 	for _, config := range p.Configs {
-		if len(config.Selection) == 0 {
-			config.Selection = "/"
-		}
 		selectedNodes, err := p.document.QueryAll(doc, config.Selection)
 		if err != nil {
 			return nil, err
@@ -213,42 +221,11 @@ func (p *Parser) parseQuery(starttime time.Time, doc, selected dataNode, config
 		if err != nil {
 			return nil, fmt.Errorf("failed to query timestamp: %v", err)
 		}
-		switch v := v.(type) {
-		case string:
-			// Parse the string with the given format or assume the string to contain
-			// a unix timestamp in seconds if no format is given.
-			if len(config.TimestampFmt) < 1 || strings.HasPrefix(config.TimestampFmt, "unix") {
-				var nanoseconds int64
-
-				t, err := strconv.ParseFloat(v, 64)
-				if err != nil {
-					return nil, fmt.Errorf("failed to parse unix timestamp: %v", err)
-				}
-
-				switch config.TimestampFmt {
-				case "unix_ns":
-					nanoseconds = int64(t)
-				case "unix_us":
-					nanoseconds = int64(t * 1e3)
-				case "unix_ms":
-					nanoseconds = int64(t * 1e6)
-				default:
-					nanoseconds = int64(t * 1e9)
-				}
-				timestamp = time.Unix(0, nanoseconds)
-			} else {
-				timestamp, err = time.Parse(config.TimestampFmt, v)
-				if err != nil {
-					return nil, fmt.Errorf("failed to query timestamp format: %v", err)
-				}
+		if v != nil {
+			timestamp, err = internal.ParseTimestamp(config.TimestampFmt, v, "")
+			if err != nil {
+				return nil, fmt.Errorf("failed to parse timestamp: %w", err)
 			}
-		case float64:
-			// Assume the value to contain a timestamp in seconds and fractions thereof.
-			timestamp = time.Unix(0, int64(v*1e9))
-		case nil:
-			// No timestamp found. Just ignore the time and use "starttime"
-		default:
-			return nil, fmt.Errorf("unknown format '%T' for timestamp query '%v'", v, config.Timestamp)
 		}
 	}
 
diff --git a/plugins/parsers/xpath/testcases/time_float_exponential/expected.out b/plugins/parsers/xpath/testcases/time_float_exponential/expected.out
new file mode 100644
index 000000000..d158287be
--- /dev/null
+++ b/plugins/parsers/xpath/testcases/time_float_exponential/expected.out
@@ -0,0 +1 @@
+time_float_exponential truth=42.0 1663830962276000
diff --git a/plugins/parsers/xpath/testcases/time_float_exponential/telegraf.conf b/plugins/parsers/xpath/testcases/time_float_exponential/telegraf.conf
new file mode 100644
index 000000000..2617a4352
--- /dev/null
+++ b/plugins/parsers/xpath/testcases/time_float_exponential/telegraf.conf
@@ -0,0 +1,12 @@
+[[inputs.file]]
+  files = ["./testcases/time_float_exponential/test.json"]
+  data_format = "xpath_json"
+  xpath_native_types = true
+
+  [[inputs.file.xpath]]
+    metric_name = "'time_float_exponential'"
+    timestamp = "t"
+    timestamp_format = "unix_ms"
+    field_selection = "."
+    field_name = "id"
+    field_value = "v"
\ No newline at end of file
diff --git a/plugins/parsers/xpath/testcases/time_float_exponential/test.json b/plugins/parsers/xpath/testcases/time_float_exponential/test.json
new file mode 100644
index 000000000..da6cd05cc
--- /dev/null
+++ b/plugins/parsers/xpath/testcases/time_float_exponential/test.json
@@ -0,0 +1,5 @@
+{
+  "id": "truth",
+  "v": 42,
+  "t": 1.663830962276e+12
+}