Evaluation
Speed, memory, correctness and cost
Bytes per token says how well a tokenizer compresses text, not whether it is fast, small, correct or cheap for a given job. 40 tokenizers measured on six separate dimensions, every number tagged as measured, estimated or unavailable.
Best tokenizer for a workload
Multilingual and mixed-language chat, parity with English, no byte fallback. Each column is a raw value, with ↑ or ↓ for the better direction; the score is the mean of their percentile ranks (1 = best).
Worst in the columnBest in the column
| # | Tokenizer | Score | Tokens, multilingual chat ↓ | Tokens, mixed-language chat ↓ | Bytes/token, languages ↑ | Parity gap vs English ↓ | Byte-fallback share ↓ |
|---|---|---|---|---|---|---|---|
| 1 | Akshara 448k | 0.99 | 51,424 | 22,958 | 7.213 | 0.254 | 0.15% |
| 2 | Akshara 248k | 0.93 | 54,663 | 24,303 | 6.592 | 0.320 | 0.25% |
| 3 | Akshara 200k | 0.88 | 56,012 | 24,928 | 6.350 | 0.347 | 0.31% |
| 4 | gemma-3-1b-it | 0.88 | 53,716 | 25,167 | 5.966 | 0.330 | 0.37% |
| 5 | 0.86 | 53,821 | 25,167 | 5.966 | 0.330 | 0.37% | |
| 6 | 0.79 | 57,827 | 25,793 | 6.019 | 0.386 | 0.40% | |
| 7 | 0.76 | 52,950 | 26,250 | 5.326 | 0.444 | 0.80% | |
| 8 | 0.75 | 53,059 | 26,596 | 5.417 | 0.402 | 1.17% | |
| 9 | 0.71 | 59,769 | 26,805 | 5.739 | 0.417 | 0.49% | |
| 10 | 0.65 | 62,101 | 27,919 | 5.419 | 0.451 | 0.64% | |
| 11 | 0.65 | 51,377 | 28,350 | 5.111 | 0.512 | 5.09% | |
| 12 | 0.57 | 57,645 | 28,794 | 4.805 | 0.514 | 1.74% | |
| 13 | 0.54 | 57,513 | 30,569 | 4.418 | 0.595 | 1.02% | |
| 14 | 0.54 | 66,162 | 29,961 | 4.906 | 0.502 | 1.07% | |
| 15 | 0.48 | 57,084 | 31,914 | 4.263 | 0.686 | 3.42% | |
| 16 | 0.46 | 68,002 | 31,005 | 4.703 | 0.520 | 1.30% | |
| 17 | 0.44 | 58,120 | 32,199 | 4.620 | 0.556 | 10.18% | |
| 18 | 0.37 | 72,421 | 33,562 | 4.240 | 0.564 | 2.15% | |
| 19 | 0.36 | 61,691 | 36,378 | 5.223 | 0.628 | 44.85% | |
| 20 | 0.34 | 66,085 | 33,845 | 3.881 | 0.692 | 3.55% | |
| 21 | 0.31 | 65,407 | 35,210 | 3.593 | 0.838 | 5.86% | |
| 22 | 0.29 | 57,233 | 42,375 | 3.309 | 0.933 | 17.66% | |
| 23 | 0.28 | 64,276 | 36,821 | 3.494 | 0.856 | 8.92% | |
| 24 | 0.28 | 60,394 | 40,321 | 3.657 | 0.864 | 18.43% | |
| 25 | 0.16 | 69,668 | 47,553 | 2.644 | 1.150 | 22.39% | |
| 26 | 0.11 | 76,201 | 56,772 | 2.388 | 1.160 | 28.87% | |
| 27 | 0.08 | 98,488 | 64,809 | 1.933 | 1.479 | 42.37% | |
| 28 | 0.03 | 110,194 | 71,477 | 1.788 | 1.605 | 53.08% | |
| 29 | 0.01 | 111,625 | 71,484 | 1.787 | 1.605 | 53.03% |
Measurements ↑ higher is better, ↓ lower is better
Speed and memory are measured on the same library for every tokenizer. Italic values are estimates (arithmetic on stated assumptions); n/a values were not measured. Hover or focus a value with a dotted underline to see its note.
| Tokenizer | Vocabulary | Bytes/token, overall ↑ | Bytes/token, English ↑ | Bytes/token, code ↑ | Bytes/token, languages ↑ | Parity gap vs English ↓ |
|---|---|---|---|---|---|---|
| 448,000 | 5.409 | 4.936 | 4.078 | 7.213 | 0.254 | |
| 248,000 | 5.141 | 4.839 | 3.991 | 6.592 | 0.320 | |
| 200,000 | 5.032 | 4.792 | 3.952 | 6.350 | 0.347 | |
| 151,000 | 4.877 | 4.719 | 3.894 | 6.019 | 0.386 | |
| 120,000 | 4.747 | 4.655 | 3.847 | 5.739 | 0.417 | |
| 92,000 | 4.589 | 4.565 | 3.782 | 5.419 | 0.451 | |
| 59,000 | 4.319 | 4.393 | 3.658 | 4.906 | 0.502 | |
| 49,000 | 4.202 | 4.306 | 3.598 | 4.703 | 0.520 | |
| 32,000 | 3.928 | 4.093 | 3.452 | 4.240 | 0.564 | |
| 32,011 | 3.170 | 4.044 | 3.077 | 2.388 | 1.160 | |
| 49,152 | 3.204 | 4.543 | 3.136 | 1.933 | 1.479 | |
| 50,257 | 2.950 | 4.659 | 2.405 | 1.787 | 1.605 | |
| 50,277 | 3.493 | 4.666 | 3.369 | 2.444 | 1.230 | |
| 50,281 | 3.216 | 4.659 | 3.202 | 1.788 | 1.605 | |
| 68,096 | 3.498 | 4.020 | 2.766 | 3.709 | 1.024 | |
| 100,277 | 3.736 | 4.691 | 3.872 | 2.644 | 1.150 | |
| 100,278 | 3.736 | 4.691 | 3.872 | 2.644 | 1.150 | |
| 100,278 | 3.736 | 4.691 | 3.872 | 2.644 | 1.150 | |
| 100,352 | 3.736 | 4.691 | 3.872 | 2.644 | 1.150 | |
| 101,304 | 3.885 | 4.401 | 3.373 | 3.881 | 0.692 | |
| 120,818 | 3.965 | 4.706 | 3.696 | 3.494 | 0.856 | |
| 125,033 | 4.213 | 4.628 | 3.594 | 4.418 | 0.595 | |
| 128,256 | 4.080 | 4.693 | 3.891 | 3.657 | 0.864 | |
| 128,815 | 4.202 | 4.732 | 3.610 | 4.263 | 0.686 | |
| 131,072 | 4.312 | 4.552 | 3.579 | 4.805 | 0.514 | |
| 151,665 | 3.903 | 4.573 | 3.793 | 3.343 | 0.894 | |
| 151,669 | 3.903 | 4.573 | 3.793 | 3.343 | 0.894 | |
| 154,856 | 3.958 | 4.685 | 3.880 | 3.309 | 0.933 | |
| 155,121 | 4.109 | 4.589 | 3.617 | 4.122 | 0.658 | |
| 157,153 | 3.920 | 4.617 | 3.669 | 3.473 | 0.870 | |
| 163,584 | 4.041 | 4.693 | 3.837 | 3.593 | 0.838 | |
| 200,019 | 4.640 | 4.742 | 3.852 | 5.326 | 0.444 | |
| 200,054 | 4.161 | 4.821 | 3.780 | 3.882 | 0.800 | |
| 204,800 | 4.584 | 4.609 | 3.727 | 5.417 | 0.402 | |
| 248,077 | 4.456 | 4.589 | 3.809 | 4.970 | 0.475 | |
| 255,033 | 4.640 | 4.888 | 3.920 | 5.111 | 0.512 | |
| 261,120 | 4.134 | 4.531 | 3.250 | 4.620 | 0.556 | |
| 262,144 | 4.710 | 4.659 | 3.505 | 5.966 | 0.330 | |
| 262,144 | 4.458 | 4.653 | 3.498 | 5.223 | 0.628 | |
| 262,145 | 4.713 | 4.659 | 3.512 | 5.966 | 0.330 |
Encode speed by input size
MB encoded per second on one thread, on the same library for every tokenizer. Higher is better.
Showing 6 of 36. Select a model to add or remove it.
Tokens per language, relative to English same FLORES-200 sentences; lower is better
Each value is a language's token count divided by English's for the same sentences: 1.00 means as many tokens as English, 2.00 twice as many. Deeper red means more tokens, so worse.
1.00 or less: as many as English4× English or more
| Tokenizer | de | fr | es | ru | zh | ja | ko | ar | ur | hi | mr | gu | bn | ta | te | th | vi | tr | id |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1.21 | 1.30 | 1.25 | 1.32 | 0.96 | 1.03 | 1.25 | 1.19 | 1.48 | 1.51 | 1.40 | 1.46 | 1.38 | 1.46 | 1.50 | 1.24 | 1.37 | 1.19 | 1.08 | |
| 1.28 | 1.34 | 1.30 | 1.44 | 1.02 | 1.10 | 1.36 | 1.28 | 1.57 | 1.62 | 1.52 | 1.59 | 1.48 | 1.61 | 1.65 | 1.37 | 1.39 | 1.29 | 1.16 | |
| 1.31 | 1.37 | 1.32 | 1.48 | 1.04 | 1.13 | 1.41 | 1.32 | 1.61 | 1.67 | 1.58 | 1.64 | 1.53 | 1.67 | 1.71 | 1.41 | 1.40 | 1.32 | 1.19 | |
| 1.35 | 1.40 | 1.36 | 1.55 | 1.08 | 1.18 | 1.48 | 1.37 | 1.66 | 1.73 | 1.67 | 1.73 | 1.59 | 1.74 | 1.82 | 1.50 | 1.42 | 1.37 | 1.24 | |
| 1.39 | 1.43 | 1.38 | 1.60 | 1.10 | 1.22 | 1.52 | 1.41 | 1.70 | 1.79 | 1.73 | 1.79 | 1.65 | 1.82 | 1.89 | 1.58 | 1.45 | 1.41 | 1.28 | |
| 1.42 | 1.46 | 1.40 | 1.66 | 1.13 | 1.25 | 1.57 | 1.46 | 1.74 | 1.86 | 1.82 | 1.87 | 1.73 | 1.89 | 1.98 | 1.66 | 1.48 | 1.45 | 1.32 | |
| 1.48 | 1.50 | 1.45 | 1.75 | 1.18 | 1.31 | 1.66 | 1.53 | 1.83 | 1.94 | 1.94 | 1.98 | 1.82 | 2.03 | 2.14 | 1.80 | 1.52 | 1.55 | 1.38 | |
| 1.49 | 1.51 | 1.46 | 1.79 | 1.19 | 1.33 | 1.68 | 1.55 | 1.87 | 1.96 | 1.99 | 2.03 | 1.87 | 2.09 | 2.18 | 1.85 | 1.56 | 1.58 | 1.40 | |
| 1.52 | 1.53 | 1.49 | 1.89 | 1.23 | 1.39 | 1.76 | 1.60 | 1.93 | 2.06 | 2.11 | 2.15 | 1.95 | 2.23 | 2.31 | 1.96 | 1.66 | 1.64 | 1.45 | |
| 1.41 | 1.46 | 1.44 | 1.66 | 2.02 | 2.25 | 3.20 | 3.47 | 4.40 | 4.61 | 4.59 | 10.00 | 5.39 | 5.91 | 10.78 | 4.37 | 2.92 | 2.09 | 1.76 | |
| 2.07 | 1.92 | 1.93 | 3.94 | 2.68 | 3.65 | 4.80 | 4.04 | 5.55 | 5.18 | 5.47 | 11.88 | 8.54 | 9.53 | 12.81 | 8.27 | 3.83 | 2.39 | 1.92 | |
| 2.13 | 1.98 | 1.97 | 5.77 | 3.20 | 2.98 | 5.05 | 4.43 | 6.29 | 7.47 | 7.86 | 12.19 | 9.62 | 15.53 | 13.14 | 8.99 | 4.53 | 2.43 | 1.97 | |
| 1.81 | 1.74 | 1.71 | 2.69 | 2.10 | 2.21 | 3.58 | 3.02 | 4.49 | 4.77 | 5.13 | 6.95 | 6.57 | 7.81 | 7.36 | 5.11 | 3.21 | 2.19 | 1.87 | |
| 2.13 | 1.98 | 1.97 | 5.77 | 3.20 | 2.98 | 5.05 | 4.43 | 6.29 | 7.47 | 7.86 | 12.19 | 9.62 | 15.53 | 13.14 | 8.99 | 4.53 | 2.43 | 1.97 | |
| 2.16 | 2.12 | 2.07 | 8.38 | 3.85 | 5.38 | 5.00 | 6.79 | 7.41 | 1.15 | 1.07 | 1.21 | 1.28 | 1.16 | 1.17 | 11.54 | 4.36 | 2.68 | 1.95 | |
| 1.58 | 1.59 | 1.54 | 2.51 | 1.90 | 2.29 | 2.39 | 3.08 | 4.41 | 4.80 | 5.07 | 7.69 | 5.85 | 7.66 | 8.43 | 4.36 | 2.45 | 1.92 | 1.55 | |
| 1.57 | 1.59 | 1.52 | 1.98 | 0.95 | 1.70 | 2.15 | 1.90 | 2.10 | 2.35 | 2.51 | 2.94 | 2.59 | 2.93 | 3.31 | 2.68 | 1.70 | 1.62 | 1.37 | |
| 1.69 | 1.66 | 1.67 | 2.13 | 0.93 | 1.63 | 1.71 | 2.03 | 3.00 | 3.40 | 3.72 | 5.16 | 3.93 | 3.88 | 5.45 | 2.47 | 1.76 | 1.79 | 1.52 | |
| 1.36 | 1.39 | 1.38 | 1.66 | 1.23 | 1.31 | 1.39 | 1.36 | 2.06 | 2.53 | 2.72 | 2.70 | 2.87 | 3.20 | 3.05 | 2.07 | 1.41 | 1.52 | 1.31 | |
| 1.58 | 1.59 | 1.54 | 1.65 | 1.30 | 1.53 | 1.50 | 1.68 | 3.12 | 2.55 | 2.80 | 7.70 | 5.81 | 7.67 | 8.43 | 2.20 | 1.39 | 1.41 | 1.54 | |
| 1.51 | 1.53 | 1.49 | 1.62 | 0.96 | 1.44 | 1.67 | 1.64 | 2.40 | 2.83 | 3.02 | 3.88 | 2.04 | 3.10 | 3.83 | 1.79 | 2.11 | 2.03 | 1.35 | |
| 1.31 | 1.31 | 1.31 | 1.54 | 1.43 | 1.58 | 1.30 | 1.27 | 1.79 | 1.82 | 2.16 | 2.75 | 2.07 | 2.20 | 2.31 | 2.37 | 1.43 | 1.49 | 1.31 | |
| 1.56 | 1.56 | 1.52 | 1.79 | 1.02 | 1.42 | 1.65 | 1.66 | 3.20 | 4.46 | 4.63 | 6.76 | 5.06 | 6.14 | 7.12 | 2.56 | 1.43 | 1.63 | 1.54 | |
| 1.44 | 1.50 | 1.43 | 1.46 | 0.97 | 1.51 | 1.95 | 1.80 | 2.78 | 4.35 | 4.59 | 7.69 | 4.75 | 7.66 | 8.42 | 4.18 | 1.46 | 1.65 | 1.54 | |
| 1.40 | 1.45 | 1.43 | 1.52 | 1.00 | 2.15 | 1.72 | 1.70 | 2.27 | 2.70 | 2.77 | 3.08 | 2.77 | 3.00 | 2.96 | 2.61 | 1.46 | 1.53 | 1.31 | |
| 1.56 | 1.58 | 1.58 | 1.76 | 0.88 | 1.51 | 1.50 | 1.82 | 3.60 | 3.83 | 4.27 | 6.98 | 2.57 | 7.01 | 6.81 | 2.29 | 1.60 | 1.65 | 1.53 | |
| 1.72 | 1.72 | 1.69 | 2.08 | 0.89 | 1.66 | 2.00 | 2.09 | 2.20 | 2.77 | 2.90 | 3.78 | 2.99 | 4.19 | 4.00 | 3.55 | 2.80 | 1.95 | 1.58 | |
| 1.31 | 1.36 | 1.31 | 1.45 | 1.27 | 1.67 | 1.48 | 1.41 | 1.69 | 1.59 | 1.83 | 1.81 | 1.72 | 2.00 | 1.96 | 1.95 | 1.49 | 1.43 | 1.24 | |
| 1.49 | 1.29 | 1.24 | 1.77 | 0.93 | 1.03 | 1.33 | 1.38 | 3.82 | 2.97 | 3.31 | 6.73 | 3.78 | 4.05 | 4.25 | 4.75 | 2.79 | 1.96 | 1.08 | |
| 1.24 | 1.28 | 1.25 | 1.41 | 1.25 | 1.65 | 1.40 | 1.32 | 1.56 | 1.61 | 1.56 | 1.77 | 1.57 | 1.73 | 1.80 | 2.40 | 1.41 | 1.32 | 1.26 | |
| 1.31 | 1.38 | 1.31 | 1.39 | 0.93 | 1.16 | 1.23 | 1.33 | 2.01 | 2.04 | 2.32 | 3.10 | 2.21 | 2.62 | 2.91 | 1.20 | 1.31 | 1.43 | 1.09 | |
| 1.31 | 1.37 | 1.33 | 1.51 | 1.11 | 1.19 | 1.22 | 1.37 | 2.03 | 1.67 | 2.38 | 5.85 | 2.04 | 2.31 | 2.49 | 1.70 | 1.36 | 1.55 | 1.08 | |
| 1.41 | 1.49 | 1.37 | 1.27 | 0.92 | 1.11 | 1.16 | 1.13 | 1.56 | 1.69 | 1.69 | 2.40 | 1.87 | 7.27 | 6.52 | 2.47 | 1.68 | 1.55 | 1.08 | |
| 1.32 | 1.38 | 1.28 | 1.39 | 1.09 | 1.21 | 1.37 | 1.49 | 1.55 | 1.32 | 1.40 | 1.87 | 1.22 | 1.48 | 1.80 | 1.60 | 1.37 | 1.37 | 1.14 | |
| 1.32 | 1.38 | 1.28 | 1.39 | 1.09 | 4.50 | 5.77 | 1.49 | 1.55 | 1.32 | 1.40 | 1.51 | 1.22 | 1.48 | 1.47 | 13.38 | 3.91 | 1.61 | 1.14 | |
| 1.32 | 1.38 | 1.28 | 1.39 | 1.09 | 1.21 | 1.37 | 1.49 | 1.55 | 1.32 | 1.40 | 1.87 | 1.22 | 1.48 | 1.80 | 1.60 | 1.37 | 1.37 | 1.14 |
About this evaluation