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UltraJSON is an ultra fast JSON encoder and decoder written in pure C with bindings for Python 2.5+ and 3.

To install it just run Pip as usual:

$ pip install ujson

Usage

May be used as a drop in replacement for most other JSON parsers for Python:

>>> import ujson
>>> ujson.dumps([{"key": "value"}, 81, True])
'[{"key":"value"},81,true]'
>>> ujson.loads("""[{"key": "value"}, 81, true]""")
[{u'key': u'value'}, 81, True]

Benchmarks

UltraJSON calls/sec compared to three other popular JSON parsers with performance gain specified below each.

Test machine:

Linux version 2.6.32-131.0.15.el6.x86_64

Versions:

  • ujson: 1.21

  • simplejson: 2.6.2

  • cjson: 1.05

  • yajl: 0.3.5

  • Python: Python 2.6.6 (r266:84292, Jul 20 2011, 10:22:43)

ujson

simplejson

cjson

yajl

Array with 256 utf-8 strings

Encode

4090,74

899,39

83,86

3189,86

4,55

48,78

1,28

Decode

863,29

586,15

201,61

352,48

1,47

4,28

2,45

Medium complex object

Encode

9750,37

1377,15

1512,06

3341,91

7,08

6,45

2,92

Decode

5576,75

4247,16

3587,83

2850,13

1,31

1,55

1,96

Array with 256 strings

Encode

17998,01

12954,46

8715,02

15924,35

1,39

2,07

1,13

Decode

14540,71

19696,13

14908,46

9547,14

0,74

0,98

1,52

Array with 256 doubles

Encode

2185,20

1466,87

1956,99

3421,10

1,49

1,12

0,64

Decode

16062,01

8990,50

9743,40

8331,74

1,79

1,65

1,93

Array with 256 True values

Encode

69767,60

25202,56

41145,99

64330,76

2,77

1,70

1,08

Decode

91416,02

56439,97

54918,09

42786,02

1,62

1,66

2,14

Array with 256 dict{string, int} pairs

Encode

11307,54

1830,45

2720,90

7725,56

6,18

4,16

1,46

Decode

8695,94

7572,89

6076,71

5231,32

1,15

1,43

1,66

Dict with 256 arrays with 256 dict

Encode

37,76

4,88

10,49

27,62

7,74

3,60

1,37

Decode

17,70

15,56

11,25

12,00

1,14

1,57

1,47

Metadata

Release files for ujson 1.23

For a detailed explanation of source distributions (sdists) and built distributions (wheels), please see the package formats documentation.

Source distribution (sdist)

Source distribution for ujson 1.23
File Size Uploaded
ujson-1.23.zip 193.7 kB Details

Built distributions (wheels)

Table of built distributions (wheels) for ujson 1.23
File Interpreter ABI Platform
ujson-1.23.win32-py3.2.exe Details
ujson-1.23.win32-py2.7.exe Details
ujson-1.23.win32-py2.6.exe Details

Total release size: 849.4 kB

Release files / ujson-1.23.zip

Download URL ujson-1.23.zip
Size 193.7 kB
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Release files / ujson-1.23.win32-py3.2.exe

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Size 218.5 kB
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Release files / ujson-1.23.win32-py2.6.exe

Download URL ujson-1.23.win32-py2.6.exe
Size 218.7 kB
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Release history Release notifications | RSS feed

5.9.0

65 release files

5.8.0

61 release files

5.5.0

65 release files

5.3.0

50 release files

5.1.0

50 release files

5.0.0

50 release files

4.3.0

44 release files

4.2.0

44 release files

4.1.0

21 release files

4.0.2

21 release files

2.0.3

7 release files

2.0.2

7 release files

2.0.1

7 release files

2.0.0

1 release file

1.35

1 release file

1.34

2 release files

1.33

3 release files

1.30

4 release files

This release

1.23 This release

4 release files

1.22

4 release files

1.21

4 release files

1.19

3 release files

1.18

1 release file

1.15

1 release file

1.9

1 release file

1.8

1 release file

1.6

1 release file

1.4

1 release file

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