RTK was documented as delivering "60-90% token savings", which reads as a cost reduction. What RTK actually reduces is bash output bytes. Those are one contributor to input tokens, which are themselves only part of a bill that also counts output tokens, so the reduction dilutes at every step. - add docs/guide/resources/savings-explained.md as the canonical explainer: the savings chain, both estimators, and what RTK does not reduce - rescope the headline claim across README (7 languages), the guide, hook rules, agent definitions and module READMEs - relabel per-command tables as bash output reduction, keeping every figure - document that reported tokens are estimates: rtk gain uses bytes/4 (src/core/tracking.rs), filter tests use split_whitespace().count(). Neither is a real tokenizer, so ratios hold but absolute counts do not Remove figures that had no source: the $3/Mtok constant and its $36 example, the +/-10% tokenization accuracy claim, the 99.5% hook-install figure, the invented session tables in README and INSTALL, and the 30-50% parser range. CHANGELOG is untouched. Shipped release notes stay as a historical record.
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title, description, sidebar
| title | description | sidebar | ||
|---|---|---|---|---|
| Token Savings Analytics | Measure and analyze the bash output reduction RTK achieves with rtk gain |
|
Token Savings Analytics
rtk gain shows how much bash output RTK has removed across all your commands, with daily, weekly, and monthly breakdowns.
What rtk gain measures is the reduction in bash output bytes, converted to estimated tokens:
Bash output bytes -> Input tokens -> Cost
what RTK filters one input source input + output tokens
among several
Bash output is one contributor to input tokens, alongside your prompt, the system prompt and conversation history. Input tokens are in turn only part of the bill, which also counts output tokens. See How RTK Savings Work for the full picture.
Quick reference
# Default summary
rtk gain
# Temporal breakdowns
rtk gain --daily # all days since tracking started
rtk gain --weekly # aggregated by week
rtk gain --monthly # aggregated by month
rtk gain --all # all breakdowns at once
# Classic flags
rtk gain --graph # ASCII graph, last 30 days
rtk gain --history # last 10 commands
rtk gain --quota # monthly quota savings estimate (default tier: 20x)
rtk gain --quota -t pro # use pro tier token budget for estimate
# Export
rtk gain --all --format json > savings.json
rtk gain --all --format csv > savings.csv
Daily breakdown
rtk gain --daily
Example output (illustrative numbers from one machine, not typical results — yours depend entirely on which commands you run):
📅 Daily Breakdown (3 days)
════════════════════════════════════════════════════════════════
Date Cmds Input Output Saved Save%
────────────────────────────────────────────────────────────────
2026-01-28 89 380.9K 26.7K 355.8K 93.4%
2026-01-29 102 894.5K 32.4K 863.7K 96.6%
2026-01-30 5 749 55 694 92.7%
────────────────────────────────────────────────────────────────
TOTAL 196 1.3M 59.2K 1.2M 95.6%
- Cmds: RTK commands executed
- Input: Estimated tokens from raw command output (
bytes / 4) - Output: Estimated tokens after filtering (
bytes / 4) - Saved: Input - Output, in estimated tokens
- Save%: Saved / Input × 100 — a bash output byte ratio, not a share of your bill
Weekly and monthly breakdowns
rtk gain --weekly
rtk gain --monthly
Same columns as daily, aggregated by Sunday-Saturday week or calendar month.
Export formats
| Format | Flag | Use case |
|---|---|---|
text |
default | Terminal display |
json |
--format json |
Programmatic analysis, dashboards |
csv |
--format csv |
Excel, Python/R, Google Sheets |
JSON structure:
{
"summary": {
"total_commands": 196,
"total_input": 1276098,
"total_output": 59244,
"total_saved": 1220217,
"avg_savings_pct": 95.62
},
"daily": [...],
"weekly": [...],
"monthly": [...]
}
Typical savings by command
| Command | Bash output reduction | Mechanism |
|---|---|---|
git status |
77-93% | Compact stat format |
eslint |
84% | Group by rule |
jest |
94-99% | Show failures only |
vitest |
94-99% | Show failures only |
find |
75% | Tree format |
pnpm list |
70-90% | Compact dependencies |
grep |
70% | Truncate + group |
These percentages measure bash output bytes removed, not cost reduction. See How RTK Savings Work.
How token estimation works
rtk gain estimates tokens as bytes / 4 (src/core/tracking.rs:1284). RTK ships no real tokenizer by design: embedding one would cost startup time and would require a tokenizer per model, or a per-session model lookup, which RTK does not implement. The same estimator is applied to raw and filtered output, so the percentage is reliable; the absolute token counts are approximate and will not match your provider's billing.
Input Tokens = estimate_tokens(raw_command_output)
Output Tokens = estimate_tokens(rtk_filtered_output)
Saved Tokens = Input - Output
Savings % = (Saved / Input) × 100
Database
Savings data is stored locally in SQLite:
- Location:
~/.local/share/rtk/history.db(Linux / macOS) - Retention: 90 days (automatic cleanup)
- Scope: Global across all projects and Claude sessions
# Inspect raw data
sqlite3 ~/.local/share/rtk/history.db \
"SELECT timestamp, rtk_cmd, saved_tokens FROM commands
ORDER BY timestamp DESC LIMIT 10"
# Backup
cp ~/.local/share/rtk/history.db ~/backups/rtk-history-$(date +%Y%m%d).db
# Reset
rm ~/.local/share/rtk/history.db # recreated on next command
Analysis workflows
# Weekly progress: generate a CSV report every Monday
rtk gain --weekly --format csv > reports/week-$(date +%Y-%W).csv
# Monthly budget review
rtk gain --monthly --format json | jq '.monthly[] |
{month, saved_tokens, quota_pct: (.saved_tokens / 6000000 * 100)}'
# Cron: daily JSON snapshot for a dashboard
0 0 * * * rtk gain --all --format json > /var/www/dashboard/rtk-stats.json
Python/pandas:
import pandas as pd
import subprocess
result = subprocess.run(['rtk', 'gain', '--all', '--format', 'csv'],
capture_output=True, text=True)
lines = result.stdout.split('\n')
daily_start = lines.index('# Daily Data') + 2
daily_end = lines.index('', daily_start)
daily_df = pd.read_csv(pd.StringIO('\n'.join(lines[daily_start:daily_end])))
daily_df['date'] = pd.to_datetime(daily_df['date'])
daily_df.plot(x='date', y='savings_pct', kind='line')
GitHub Actions (weekly stats):
on:
schedule:
- cron: '0 0 * * 1'
jobs:
stats:
runs-on: ubuntu-latest
steps:
- uses: actions/checkout@v3
- run: cargo install --git https://github.com/rtk-ai/rtk --branch master rtk
- run: rtk gain --weekly --format json > stats/week-$(date +%Y-%W).json
- run: git add stats/ && git commit -m "Weekly rtk stats" && git push
Quota estimate
--quota expresses the estimated tokens saved as a fraction of a monthly subscription budget. Like every other figure in rtk gain, it is derived from the bytes / 4 estimate of bash output, so treat it as an order of magnitude rather than a billing forecast.
rtk gain --quota # uses 20x tier by default
rtk gain --quota -t pro # Claude Pro plan budget
rtk gain --quota -t 5x # 5× usage plan budget
rtk gain --quota -t 20x # 20× usage plan budget
The tiers (pro, 5x, 20x) correspond to Anthropic Claude API subscription levels, each with a different monthly token allocation. RTK uses those allocations as a denominator to express your savings as a percentage of your budget.
:::tip[Find missed savings]
rtk gain shows what RTK saved. To find commands that ran without RTK and calculate what you lost, see rtk discover.
:::
Troubleshooting
No data showing:
ls -lh ~/.local/share/rtk/history.db
sqlite3 ~/.local/share/rtk/history.db "SELECT COUNT(*) FROM commands"
git status # run any tracked command to generate data
Incorrect statistics: Token estimation is a heuristic. For precise counts, use tiktoken:
pip install tiktoken
git status > output.txt
python -c "
import tiktoken
enc = tiktoken.get_encoding('cl100k_base')
print(len(enc.encode(open('output.txt').read())), 'actual tokens')
"